[maven-release-plugin] prepare release avaje-ebeanorm-6.18.1

Add test for broken fetching issue #462

.gitignore

@@ -1,5 +1,6 @@
 *.autofetch
-*.sql
+*create-all.sql
+*drop-all.sql
 *.orig
 .classpath
 .project

pom.xml

@@ -9,7 +9,7 @@
 
   <groupId>org.avaje.ebeanorm</groupId>
   <artifactId>avaje-ebeanorm</artifactId>
-  <version>6.16.3</version>
+  <version>6.18.1</version>
   <packaging>jar</packaging>
 
   <name>avaje-ebeanorm</name>

src/main/java/com/avaje/ebean/DRawSqlParser.java

@@ -71,7 +71,7 @@ class DRawSqlParser {
 
     preFrom = trimSelectKeyword(preFrom);
 
-    return new Sql(sql.hashCode(), preFrom, preWhere, whereExprAnd, preHaving, havingExprAnd, orderByPrefix, orderBySql, (distinctPos > -1));
+    return new Sql(sql, preFrom, preWhere, whereExprAnd, preHaving, havingExprAnd, orderByPrefix, orderBySql, (distinctPos > -1));
   }
 
   /**

src/main/java/com/avaje/ebean/FetchConfig.java

@@ -249,4 +249,22 @@ public class FetchConfig implements Serializable {
     return queryAll;
   }
 
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+
+    FetchConfig that = (FetchConfig) o;
+    if (lazyBatchSize != that.lazyBatchSize) return false;
+    if (queryBatchSize != that.queryBatchSize) return false;
+    return queryAll == that.queryAll;
+  }
+
+  @Override
+  public int hashCode() {
+    int result = lazyBatchSize;
+    result = 92821 * result + queryBatchSize;
+    result = 92821 * result + (queryAll ? 1 : 0);
+    return result;
+  }
 }

src/main/java/com/avaje/ebean/RawSql.java

@@ -206,6 +206,14 @@ public final class RawSql implements Serializable {
     return sql;
   }
 
+  /**
+   * Return the key;
+   */
+  public Key getKey() {
+    boolean parsed = sql != null && sql.parsed;
+    String unParsedSql = (sql == null) ? "" : sql.unparsedSql;
+    return new Key(parsed, unParsedSql, columnMapping);
+  }
   
   /**
    * Return the resultSet if this is a ResultSet based RawSql.
@@ -221,16 +229,6 @@ public final class RawSql implements Serializable {
     return columnMapping;
   }
 
-  /**
-   * Return the hash for this query.
-   */
-  public int queryHash() {
-    if (resultSet != null) {
-      return 31 * columnMapping.queryHash();
-    }
-    return 31 * sql.queryHash() + columnMapping.queryHash();
-  }
-
   /**
    * Represents the sql part of the query. For parsed RawSql the sql is broken
    * up so that Ebean can insert extra WHERE and HAVING expressions into the
@@ -260,13 +258,10 @@ public final class RawSql implements Serializable {
 
     private final boolean distinct;
 
-    private final int queryHashCode;
-
     /**
      * Construct for unparsed SQL.
      */
     protected Sql(String unparsedSql) {
-      this.queryHashCode = unparsedSql.hashCode();
       this.parsed = false;
       this.unparsedSql = unparsedSql;
       this.preFrom = null;
@@ -282,12 +277,11 @@ public final class RawSql implements Serializable {
     /**
      * Construct for parsed SQL.
      */
-    protected Sql(int queryHashCode, String preFrom, String preWhere, boolean andWhereExpr,
+    protected Sql(String unparsedSql, String preFrom, String preWhere, boolean andWhereExpr,
         String preHaving, boolean andHavingExpr, String orderByPrefix, String orderBy, boolean distinct) {
 
-      this.queryHashCode = queryHashCode;
+      this.unparsedSql = unparsedSql;
       this.parsed = true;
-      this.unparsedSql = null;
       this.preFrom = preFrom;
       this.preHaving = preHaving;
       this.preWhere = preWhere;
@@ -298,13 +292,6 @@ public final class RawSql implements Serializable {
       this.distinct = distinct;
     }
 
-    /**
-     * Return a hash for this query.
-     */
-    public int queryHash() {
-      return queryHashCode;
-    }
-
     public String toString() {
       if (!parsed) {
         return "unparsed[" + unparsedSql + "]";
@@ -406,13 +393,10 @@ public final class RawSql implements Serializable {
 
     private final boolean immutable;
 
-    private final int queryHashCode;
-
     /**
      * Construct from parsed sql where the columns have been identified.
      */
     protected ColumnMapping(List<Column> columns) {
-      this.queryHashCode = 0;
       this.immutable = false;
       this.parsed = true;
       this.propertyMap = null;
@@ -428,7 +412,6 @@ public final class RawSql implements Serializable {
      * Construct for unparsed sql.
      */
     protected ColumnMapping() {
-      this.queryHashCode = 0;
       this.immutable = false;
       this.parsed = false;
       this.propertyMap = null;
@@ -443,17 +426,13 @@ public final class RawSql implements Serializable {
       this.immutable = false;
       this.parsed = false;
       this.propertyMap = null;
-      //this.propertyColumnMap = null;
       this.dbColumnMap = new LinkedHashMap<String, Column>();
-      
-      int hc = 31;
+
       int pos = 0;
       for (String prop : propertyNames) {
-        hc = 31 * hc + prop.hashCode();
         dbColumnMap.put(prop, new Column(pos++, prop, null, prop));
       }
       propertyColumnMap = dbColumnMap;
-      this.queryHashCode = hc;
     }
 
     /**
@@ -464,20 +443,28 @@ public final class RawSql implements Serializable {
       this.parsed = parsed;
       this.dbColumnMap = dbColumnMap;
 
-      int hc = ColumnMapping.class.getName().hashCode();
-
       HashMap<String, Column> pcMap = new HashMap<String, Column>();
       HashMap<String, String> pMap = new HashMap<String, String>();
 
       for (Column c : dbColumnMap.values()) {
         pMap.put(c.getPropertyName(), c.getDbColumn());
         pcMap.put(c.getPropertyName(), c);
-        hc = 31 * hc + ((c.getPropertyName() == null) ? 0 : c.getPropertyName().hashCode());
-        hc = 31 * hc + ((c.getDbColumn() == null) ? 0 : c.getDbColumn().hashCode());
       }
       this.propertyMap = Collections.unmodifiableMap(pMap);
       this.propertyColumnMap = Collections.unmodifiableMap(pcMap);
-      this.queryHashCode = hc;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+      if (this == o) return true;
+      if (o == null || getClass() != o.getClass()) return false;
+      ColumnMapping that = (ColumnMapping) o;
+      return dbColumnMap.equals(that.dbColumnMap);
+    }
+
+    @Override
+    public int hashCode() {
+      return dbColumnMap.hashCode();
     }
 
     /**
@@ -521,16 +508,6 @@ public final class RawSql implements Serializable {
       }
     }
 
-    /**
-     * Return the query hash for this column mapping.
-     */
-    public int queryHash() {
-      if (queryHashCode == 0) {
-        throw new RuntimeException("Bug: queryHashCode == 0");
-      }
-      return queryHashCode;
-    }
-
     /**
      * Returns true if the Columns where supplied by parsing the sql select
      * clause.
@@ -585,6 +562,9 @@ public final class RawSql implements Serializable {
      * <p>
      * For example modify all mappings with table alias "c" to have the path prefix "customer".
      * </p>
+     * <p>
+     * For the "Root type" you don't need to specify a tableAliasMapping.
+     * </p>
      */
     public void tableAliasMapping(String tableAlias, String path) {
 
@@ -645,6 +625,27 @@ public final class RawSql implements Serializable {
         }
       }
 
+      @Override
+      public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        Column that = (Column) o;
+        if (indexPos != that.indexPos) return false;
+        if (!dbColumn.equals(that.dbColumn)) return false;
+        if (dbAlias != null ? !dbAlias.equals(that.dbAlias) : that.dbAlias != null) return false;
+        return propertyName != null ? propertyName.equals(that.propertyName) : that.propertyName == null;
+      }
+
+      @Override
+      public int hashCode() {
+        int result = indexPos;
+        result = 31 * result + dbColumn.hashCode();
+        result = 31 * result + (dbAlias != null ? dbAlias.hashCode() : 0);
+        result = 31 * result + (propertyName != null ? propertyName.hashCode() : 0);
+        return result;
+      }
+
       public String toString() {
         return dbColumn + "->" + propertyName;
       }
@@ -696,4 +697,39 @@ public final class RawSql implements Serializable {
       }
     }
   }
+
+  /**
+   * A key for the RawSql object using for the query plan.
+   */
+  public static final class Key {
+
+    private final boolean parsed;
+    private final ColumnMapping columnMapping;
+    private final String unParsedSql;
+
+    Key(boolean parsed, String unParsedSql, ColumnMapping columnMapping) {
+      this.parsed = parsed;
+      this.unParsedSql = unParsedSql;
+      this.columnMapping = columnMapping;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+      if (this == o) return true;
+      if (o == null || getClass() != o.getClass()) return false;
+
+      Key that = (Key) o;
+      return parsed == that.parsed
+          && columnMapping.equals(that.columnMapping)
+          && unParsedSql.equals(that.unParsedSql);
+    }
+
+    @Override
+    public int hashCode() {
+      int result = (parsed ? 1 : 0);
+      result = 31 * result + columnMapping.hashCode();
+      result = 31 * result + unParsedSql.hashCode();
+      return result;
+    }
+  }
 }

src/main/java/com/avaje/ebean/RawSqlBuilder.java

@@ -106,6 +106,9 @@ public class RawSqlBuilder {
    * <p>
    * For example modify all mappings with table alias "c" to have the path prefix "customer".
    * </p>
+   * <p>
+   * For the "Root type" you don't need to specify a tableAliasMapping.
+   * </p>
    */
   public RawSqlBuilder tableAliasMapping(String tableAlias, String path) {
     columnMapping.tableAliasMapping(tableAlias, path);

src/main/java/com/avaje/ebean/bean/BeanCollection.java

@@ -125,6 +125,11 @@ public interface BeanCollection<E> extends Serializable {
    */
   void internalAdd(Object bean);
 
+  /**
+   * Add the bean with a check to see if it is already contained.
+   */
+  void internalAddWithCheck(Object bean);
+
   /**
    * Return the number of elements in the List Set or Map.
    */

src/main/java/com/avaje/ebean/common/BeanList.java

@@ -1,5 +1,9 @@
 package com.avaje.ebean.common;
 
+import com.avaje.ebean.bean.BeanCollectionAdd;
+import com.avaje.ebean.bean.BeanCollectionLoader;
+import com.avaje.ebean.bean.EntityBean;
+
 import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -8,17 +12,13 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.ListIterator;
 
-import com.avaje.ebean.bean.BeanCollectionAdd;
-import com.avaje.ebean.bean.BeanCollectionLoader;
-import com.avaje.ebean.bean.EntityBean;
-
 /**
  * List capable of lazy loading.
  */
 public final class BeanList<E> extends AbstractBeanCollection<E> implements List<E>, BeanCollectionAdd {
 
   private static final long serialVersionUID = 1L;
-  
+
   /**
    * The underlying List implementation.
    */
@@ -74,6 +74,13 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
     }
   }
 
+  @Override
+  public void internalAddWithCheck(Object bean) {
+    if (list == null || !list.contains(bean)) {
+      internalAdd(bean);
+    }
+  }
+
   public boolean checkEmptyLazyLoad() {
     if (list == null) {
       list = new ArrayList<E>();
@@ -99,11 +106,11 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   private void initAsUntouched() {
     init(false);
   }
-  
+
   private void init() {
     init(true);
   }
-  
+
   private void init(boolean setTouched) {
     synchronized (this) {
       if (list == null) {
@@ -134,7 +141,7 @@ public final class BeanList<E> extends AbstractBeanCollection<E> implements List
   public Collection<E> getActualDetails() {
     return list;
   }
-  
+
   @Override
   public Collection<?> getActualEntries() {
     return list;

src/main/java/com/avaje/ebean/common/BeanMap.java

@@ -66,7 +66,18 @@ public final class BeanMap<K, E> extends AbstractBeanCollection<E> implements Ma
       map.put((K) key, (E) bean);
     }
   }
-  
+
+  public void internalPutWithCheck(Object key, Object bean) {
+    if (map == null || !map.containsKey(key)) {
+      internalPut(key, bean);
+    }
+  }
+
+  @Override
+  public void internalAddWithCheck(Object bean) {
+    throw new RuntimeException("Not allowed for map");
+  }
+
   public void internalAdd(Object bean) {
     throw new RuntimeException("Not allowed for map");
   }

src/main/java/com/avaje/ebean/common/BeanSet.java

@@ -1,15 +1,15 @@
 package com.avaje.ebean.common;
 
+import com.avaje.ebean.bean.BeanCollectionAdd;
+import com.avaje.ebean.bean.BeanCollectionLoader;
+import com.avaje.ebean.bean.EntityBean;
+
 import java.io.Serializable;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.LinkedHashSet;
 import java.util.Set;
 
-import com.avaje.ebean.bean.BeanCollectionAdd;
-import com.avaje.ebean.bean.BeanCollectionLoader;
-import com.avaje.ebean.bean.EntityBean;
-
 /**
  * Set capable of lazy loading.
  */
@@ -57,6 +57,13 @@ public final class BeanSet<E> extends AbstractBeanCollection<E> implements Set<E
     set.add((E) bean);
   }
 
+  @Override
+  public void internalAddWithCheck(Object bean) {
+    if (set == null || !set.contains(bean)) {
+      internalAdd(bean);
+    }
+  }
+
   @SuppressWarnings("unchecked")
   public void internalAdd(Object bean) {
     if (set == null) {
@@ -107,11 +114,11 @@ public final class BeanSet<E> extends AbstractBeanCollection<E> implements Set<E
   private void initAsUntouched() {
     init(false);
   }
-  
+
   private void init() {
     init(true);
   }
-  
+
   private void init(boolean setTouched) {
     synchronized (this) {
       if (set == null) {

src/main/java/com/avaje/ebean/config/DbMigrationConfig.java

@@ -23,11 +23,6 @@ public class DbMigrationConfig {
    */
   protected boolean generate;
 
-  /**
-   * Set to true to suppress the output of the rollback script.
-   */
-  protected boolean suppressRollback;
-
   /**
    * The migration version name (typically FlywayDb compatible).
    * <p>
@@ -61,35 +56,17 @@ public class DbMigrationConfig {
    */
   protected String modelPath = "model";
 
-  /**
-   * Subdirectory the drop ddl scripts go into.
-   */
-  protected String dropPath = "drop";
-
-  /**
-   * Subdirectory the rollback ddl scripts go into.
-   */
-  protected String rollbackPath = "rollback";
-
-  /**
-   * Apply script suffix.
-   */
   protected String applySuffix = ".sql";
 
-  /**
-   * Default drop script suffix to ddl so that it isn't picked up by FlywayDb.
-   */
-  protected String dropSuffix = ".drop.ddl";
-
-  /**
-   * Default rollback script suffix to ddl so that it isn't picked up by FlywayDb.
-   */
-  protected String rollbackSuffix = ".rollback.ddl";
-
   protected String modelSuffix = ".model.xml";
 
   protected boolean includeGeneratedFileComment;
 
+  /**
+   * The version of a pending drop that should be generated as the next migration.
+   */
+  protected String generatePendingDrop;
+
   /**
    * Return the DB platform to generate migration DDL for.
    *
@@ -140,34 +117,6 @@ public class DbMigrationConfig {
     this.modelPath = modelPath;
   }
 
-  /**
-   * Return the relative path for the drop ddl scripts (defaults to drop).
-   */
-  public String getDropPath() {
-    return dropPath;
-  }
-
-  /**
-   * Set the relative path for the drop ddl scripts (defaults to drop).
-   */
-  public void setDropPath(String dropPath) {
-    this.dropPath = dropPath;
-  }
-
-  /**
-   * Return the relative path for the rollback ddl scripts (defaults to rollback).
-   */
-  public String getRollbackPath() {
-    return rollbackPath;
-  }
-
-  /**
-   * Set the relative path for the rollback ddl scripts (defaults to rollback).
-   */
-  public void setRollbackPath(String rollbackPath) {
-    this.rollbackPath = rollbackPath;
-  }
-
   /**
    * Return the model suffix (defaults to model.xml)
    */
@@ -182,20 +131,6 @@ public class DbMigrationConfig {
     this.modelSuffix = modelSuffix;
   }
 
-  /**
-   * Return true if the rollback script should not be output.
-   */
-  public boolean isSuppressRollback() {
-    return suppressRollback;
-  }
-
-  /**
-   * Set to true to suppress the output of the rollback script.
-   */
-  public void setSuppressRollback(boolean suppressRollback) {
-    this.suppressRollback = suppressRollback;
-  }
-
   /**
    * Return the apply script suffix (defaults to sql).
    */
@@ -210,34 +145,6 @@ public class DbMigrationConfig {
     this.applySuffix = applySuffix;
   }
 
-  /**
-   * Return the drop script suffix (defaults to ddl so that it isn't picked up by FlywayDb).
-   */
-  public String getDropSuffix() {
-    return dropSuffix;
-  }
-
-  /**
-   * Set the drop script suffix (defaults to ddl so that it isn't picked up by FlywayDb).
-   */
-  public void setDropSuffix(String dropSuffix) {
-    this.dropSuffix = dropSuffix;
-  }
-
-  /**
-   * Return the rollback script suffix (defaults to ddl so that it isn't picked up by FlywayDb).
-   */
-  public String getRollbackSuffix() {
-    return rollbackSuffix;
-  }
-
-  /**
-   * Set the rollback script suffix (defaults to ddl so that it isn't picked up by FlywayDb).
-   */
-  public void setRollbackSuffix(String rollbackSuffix) {
-    this.rollbackSuffix = rollbackSuffix;
-  }
-
   /**
    * Return true if the generated file comment should be included.
    */
@@ -252,6 +159,20 @@ public class DbMigrationConfig {
     this.includeGeneratedFileComment = includeGeneratedFileComment;
   }
 
+  /**
+   * Return the migration version (or "next") to generate pending drops for.
+   */
+  public String getGeneratePendingDrop() {
+    return generatePendingDrop;
+  }
+
+  /**
+   * Set the migration version (or "next") to generate pending drops for.
+   */
+  public void setGeneratePendingDrop(String generatePendingDrop) {
+    this.generatePendingDrop = generatePendingDrop;
+  }
+
   /**
    * Set the migration version.
    * <p>
@@ -275,8 +196,6 @@ public class DbMigrationConfig {
    * into a single directory.
    */
   public void singleDirectory() {
-    this.dropPath = "";
-    this.rollbackPath = "";
     this.modelPath = "";
   }
 
@@ -290,17 +209,13 @@ public class DbMigrationConfig {
       singleDirectory();
     } else {
       modelPath = properties.get("migration.modelPath", modelPath);
-      rollbackPath = properties.get("migration.rollbackPath", rollbackPath);
-      dropPath = properties.get("migration.dropPath", dropPath);
     }
     applySuffix = properties.get("migration.applySuffix", applySuffix);
-    dropSuffix = properties.get("migration.dropSuffix", dropSuffix);
-    rollbackSuffix = properties.get("migration.rollbackSuffix", rollbackSuffix);
     modelSuffix = properties.get("migration.modelSuffix", modelSuffix);
     includeGeneratedFileComment = properties.getBoolean("migration.includeGeneratedFileComment", includeGeneratedFileComment);
+    generatePendingDrop = properties.get("migration.generatePendingDrop", generatePendingDrop);
 
     platform = properties.getEnum(DbPlatformName.class, "migration.platform", platform);
-    suppressRollback = properties.getBoolean("migration.suppressRollback", suppressRollback);
 
     generate = properties.getBoolean("migration.generate", generate);
     version = properties.get("migration.version", version);
@@ -324,7 +239,6 @@ public class DbMigrationConfig {
     return generate;
   }
 
-
   /**
    * Called by EbeanServer on start.
    *

src/main/java/com/avaje/ebean/config/ServerConfig.java

@@ -387,6 +387,8 @@ public class ServerConfig {
    */
   private boolean expressionEqualsWithNullAsNoop;
 
+  private String jodaLocalTimeMode;
+
   /**
    * Construct a Server Configuration for programmatically creating an EbeanServer.
    */
@@ -1640,6 +1642,20 @@ public class ServerConfig {
     this.disableClasspathSearch = disableClasspathSearch;
   }
 
+  /**
+   * Return the mode to use for Joda LocalTime support 'normal' or 'utc'.
+   */
+  public String getJodaLocalTimeMode() {
+    return jodaLocalTimeMode;
+  }
+
+  /**
+   * Set the mode to use for Joda LocalTime support 'normal' or 'utc'.
+   */
+  public void setJodaLocalTimeMode(String jodaLocalTimeMode) {
+    this.jodaLocalTimeMode = jodaLocalTimeMode;
+  }
+
   /**
    * Programmatically add classes (typically entities) that this server should
    * use.
@@ -2286,6 +2302,7 @@ public class ServerConfig {
       dbUuid = DbUuid.BINARY;
     }
     localTimeWithNanos = p.getBoolean("localTimeWithNanos", localTimeWithNanos);
+    jodaLocalTimeMode = p.get("jodaLocalTimeMode", jodaLocalTimeMode);
 
     lazyLoadBatchSize = p.getInt("lazyLoadBatchSize", lazyLoadBatchSize);
     queryBatchSize = p.getInt("queryBatchSize", queryBatchSize);

src/main/java/com/avaje/ebean/dbmigration/DbMigration.java

@@ -20,6 +20,7 @@ import com.avaje.ebean.dbmigration.migrationreader.MigrationXmlWriter;
 import com.avaje.ebean.dbmigration.model.CurrentModel;
 import com.avaje.ebean.dbmigration.model.MConfiguration;
 import com.avaje.ebean.dbmigration.model.MigrationModel;
+import com.avaje.ebean.dbmigration.model.MigrationVersion;
 import com.avaje.ebean.dbmigration.model.ModelContainer;
 import com.avaje.ebean.dbmigration.model.ModelDiff;
 import com.avaje.ebean.dbmigration.model.PlatformDdlWriter;
@@ -201,46 +202,15 @@ public class DbMigration {
     if (!online) {
       DbOffline.setRunningMigration();
     }
-
     setDefaults();
-
     try {
+      Request request = createRequest();
 
-      File migrationDir = getMigrationDirectory();
-      File modelDir = getModelDirectory(migrationDir);
-
-      MigrationModel migrationModel = new MigrationModel(modelDir, migrationConfig.getModelSuffix());
-      ModelContainer migrated = migrationModel.read();
-
-      CurrentModel currentModel = new CurrentModel(server, constraintNaming);
-      ModelContainer current = currentModel.read();
-
-      ModelDiff diff = new ModelDiff(migrated);
-      diff.compareTo(current);
-
-      if (diff.isEmpty()) {
-        logger.info("no changes detected - no migration written");
-        return;
-      }
-
-      // there were actually changes to write
-      Migration dbMigration = diff.getMigration();
-
-      String fullVersion = getFullVersion(migrationModel);
-
-      logger.info("generating migration:{}", fullVersion);
-      if (!writeMigrationXml(dbMigration, modelDir, fullVersion)) {
-        logger.warn("migration already exists, not generating DDL");
-
+      String pendingVersion = generatePendingDrop();
+      if (pendingVersion != null) {
+        generatePendingDrop(request, pendingVersion);
       } else {
-        if (databasePlatform != null) {
-          // writer needs the current model to provide table/column details for
-          // history ddl generation (triggers, history tables etc)
-          DdlWrite write = new DdlWrite(new MConfiguration(), currentModel.read());
-          PlatformDdlWriter writer = createDdlWriter(databasePlatform, "");
-          writer.processMigration(dbMigration, write, migrationDir , fullVersion);
-        }
-        writeExtraPlatformDdl(fullVersion, currentModel, dbMigration, migrationDir);
+        generateDiff(request);
       }
 
     } finally {
@@ -251,9 +221,128 @@ public class DbMigration {
   }
 
   /**
-   * Return the full version for the migration being generated.
+   * Generate the diff migration.
    */
-  private String getFullVersion(MigrationModel migrationModel) {
+  private void generateDiff(Request request) throws IOException {
+
+    List<String> pendingDrops = request.getPendingDrops();
+    if (!pendingDrops.isEmpty()) {
+      logger.info("Pending un-applied drops in versions {}", pendingDrops);
+    }
+
+    Migration migration = request.createDiffMigration();
+    if (migration == null) {
+      logger.info("no changes detected - no migration written");
+    } else {
+      // there were actually changes to write
+      generateMigration(request, migration, null);
+    }
+  }
+
+  /**
+   * Generate the migration based on the pendingDrops from a prior version.
+   */
+  private void generatePendingDrop(Request request, String pendingVersion) throws IOException {
+
+    Migration migration = request.migrationForPendingDrop(pendingVersion);
+
+    generateMigration(request, migration, pendingVersion);
+
+    List<String> pendingDrops = request.getPendingDrops();
+    if (!pendingDrops.isEmpty()) {
+      logger.info("... remaining pending un-applied drops in versions {}", pendingDrops);
+    }
+  }
+
+  private Request createRequest() {
+    return new Request();
+  }
+
+  private class Request {
+
+    final File migrationDir;
+    final File modelDir;
+    final MigrationModel migrationModel;
+    final CurrentModel currentModel;
+    final ModelContainer migrated;
+    final ModelContainer current;
+
+    private Request() {
+      this.migrationDir = getMigrationDirectory();
+      this.modelDir = getModelDirectory(migrationDir);
+      this.migrationModel = new MigrationModel(modelDir, migrationConfig.getModelSuffix());
+      this.migrated = migrationModel.read();
+      this.currentModel = new CurrentModel(server, constraintNaming);
+      this.current = currentModel.read();
+    }
+
+    /**
+     * Return the migration for the pending drops for a given version.
+     */
+    public Migration migrationForPendingDrop(String pendingVersion) {
+
+      Migration migration = migrated.migrationForPendingDrop(pendingVersion);
+
+      // register any remaining pending drops
+      migrated.registerPendingHistoryDropColumns(current);
+      return migration;
+    }
+
+    /**
+     * Return the list of versions that have pending un-applied drops.
+     */
+    public List<String> getPendingDrops() {
+      return migrated.getPendingDrops();
+    }
+
+    /**
+     * Create and return the diff of the current model to the migration model.
+     */
+    public Migration createDiffMigration() {
+      ModelDiff diff = new ModelDiff(migrated);
+      diff.compareTo(current);
+      return diff.isEmpty() ? null : diff.getMigration();
+    }
+  }
+
+  private void generateMigration(Request request, Migration dbMigration, String dropsFor) throws IOException {
+
+    String fullVersion = getFullVersion(request.migrationModel, dropsFor);
+
+    logger.info("generating migration:{}", fullVersion);
+    if (!writeMigrationXml(dbMigration, request.modelDir, fullVersion)) {
+      logger.warn("migration already exists, not generating DDL");
+
+    } else {
+      if (databasePlatform != null) {
+        // writer needs the current model to provide table/column details for
+        // history ddl generation (triggers, history tables etc)
+        DdlWrite write = new DdlWrite(new MConfiguration(), request.current);
+        PlatformDdlWriter writer = createDdlWriter(databasePlatform, "");
+        writer.processMigration(dbMigration, write, request.migrationDir , fullVersion);
+      }
+      writeExtraPlatformDdl(fullVersion, request.currentModel, dbMigration, request.migrationDir);
+    }
+  }
+
+  /**
+   * Return true if the next pending drop changeSet should be generated as the next migration.
+   */
+  private String generatePendingDrop() {
+
+    String nextDrop = System.getProperty("ddl.migration.pendingDropsFor");
+    if (nextDrop != null) {
+      return nextDrop;
+    }
+    return migrationConfig.getGeneratePendingDrop();
+  }
+
+  /**
+   * Return the full version for the migration being generated.
+   *
+   * The full version can contain a comment suffix after a "__" double underscore.
+   */
+  private String getFullVersion(MigrationModel migrationModel, String dropsFor) {
 
     String version = migrationConfig.getVersion();
     if (version == null) {
@@ -261,10 +350,14 @@ public class DbMigration {
     }
 
     String fullVersion = version;
+    if (migrationConfig.getName() != null) {
+      fullVersion += "__" + toUnderScore(migrationConfig.getName());
 
-    String name = migrationConfig.getName();
-    if (name != null) {
-      fullVersion += "__" + toUnderScore(name);
+    } else if (dropsFor != null) {
+      fullVersion += "__" + toUnderScore("dropsFor_" + MigrationVersion.trim(dropsFor));
+
+    } else if (version.equals(initialVersion)) {
+      fullVersion += "__initial";
     }
     return fullVersion;
   }

src/main/java/com/avaje/ebean/dbmigration/DdlGenerator.java

@@ -2,7 +2,6 @@ package com.avaje.ebean.dbmigration;
 
 import com.avaje.ebean.config.ServerConfig;
 import com.avaje.ebean.dbmigration.model.CurrentModel;
-import com.avaje.ebeaninternal.api.SpiEbeanPlugin;
 import com.avaje.ebeaninternal.api.SpiEbeanServer;
 
 import javax.persistence.PersistenceException;
@@ -30,8 +29,8 @@ public class DdlGenerator {
   private final boolean createOnly;
 
   private CurrentModel currentModel;
-  private String dropContent;
-  private String createContent;
+  private String dropAllContent;
+  private String createAllContent;
 
   public DdlGenerator(SpiEbeanServer server, ServerConfig serverConfig) {
     this.server = server;
@@ -84,18 +83,18 @@ public class DdlGenerator {
 
   protected void runDropSql() throws IOException {
     if (!createOnly) {
-      if (dropContent == null) {
-        dropContent = readFile(getDropFileName());
+      if (dropAllContent == null) {
+        dropAllContent = readFile(getDropFileName());
       }
-      runScript(true, dropContent, getDropFileName());
+      runScript(true, dropAllContent, getDropFileName());
     }
   }
 
   protected void runCreateSql() throws IOException {
-    if (createContent == null) {
-      createContent = readFile(getCreateFileName());
+    if (createAllContent == null) {
+      createAllContent = readFile(getCreateFileName());
     }
-    runScript(false, createContent, getCreateFileName());
+    runScript(false, createAllContent, getCreateFileName());
   }
 
   protected void runInitSql() throws IOException {
@@ -132,8 +131,7 @@ public class DdlGenerator {
   protected void writeDrop(String dropFile) {
 
     try {
-      String c = generateDropDdl();
-      writeFile(dropFile, c);
+      writeFile(dropFile, generateDropAllDdl());
     } catch (IOException e) {
       throw new PersistenceException("Error generating Drop DDL", e);
     }
@@ -142,28 +140,27 @@ public class DdlGenerator {
   protected void writeCreate(String createFile) {
 
     try {
-      String c = generateCreateDdl();
-      writeFile(createFile, c);
+      writeFile(createFile, generateCreateAllDdl());
     } catch (IOException e) {
       throw new PersistenceException("Error generating Create DDL", e);
     }
   }
 
-  protected String generateDropDdl() {
+  protected String generateDropAllDdl() {
 
     try {
-      dropContent = currentModel().getDropDdl();
-      return dropContent;
+      dropAllContent = currentModel().getDropAllDdl();
+      return dropAllContent;
     } catch (IOException e) {
       throw new RuntimeException(e);
     }
   }
 
-  protected String generateCreateDdl() {
+  protected String generateCreateAllDdl() {
 
     try {
-      createContent = currentModel().getCreateDdl();
-      return createContent;
+      createAllContent = currentModel().getCreateDdl();
+      return createAllContent;
     } catch (IOException e) {
       throw new RuntimeException(e);
     }

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/DdlWrite.java

@@ -12,32 +12,17 @@ public class DdlWrite {
 
   private final ModelContainer currentModel;
 
+  private final DdlBuffer applyDropDependencies;
+
   private final DdlBuffer apply;
 
   private final DdlBuffer applyForeignKeys;
 
   private final DdlBuffer applyHistory;
 
-  private final DdlBuffer rollbackForeignKeys;
+  private final DdlBuffer dropAllForeignKeys;
 
-  private final DdlBuffer rollback;
-
-  /**
-   * For DDL that drops tables and columns etc.
-   *
-   * This DDL typically can not run automatically in production as there is most commonly
-   * existing servers running the application using these tables and columns. Typically
-   * these drop statements may be executed AFTER all the servers in the application have
-   * migrated onto new code.
-   */
-  private final DdlBuffer drop;
-
-  /**
-   * For use when History is turned off for a base table or history is no longer
-   * desired on specific columns. This DDL should typically execute manually after review
-   * by DBA's.
-   */
-  private final DdlBuffer dropHistory;
+  private final DdlBuffer dropAll;
 
   /**
    * Create without any configuration or current model (no history support).
@@ -51,13 +36,12 @@ public class DdlWrite {
    */
   public DdlWrite(MConfiguration configuration, ModelContainer currentModel) {
     this.currentModel = currentModel;
+    this.applyDropDependencies = new BaseDdlBuffer(configuration);
     this.apply = new BaseDdlBuffer(configuration);
     this.applyForeignKeys = new BaseDdlBuffer(configuration);
     this.applyHistory = new BaseDdlBuffer(configuration);
-    this.rollbackForeignKeys = new BaseDdlBuffer(configuration);
-    this.rollback = new BaseDdlBuffer(configuration);
-    this.drop = new BaseDdlBuffer(configuration);
-    this.dropHistory = new BaseDdlBuffer(configuration);
+    this.dropAllForeignKeys = new BaseDdlBuffer(configuration);
+    this.dropAll = new BaseDdlBuffer(configuration);
   }
 
   /**
@@ -77,22 +61,8 @@ public class DdlWrite {
   public boolean isApplyEmpty() {
     return apply.getBuffer().isEmpty()
         && applyForeignKeys.getBuffer().isEmpty()
-        && applyHistory.getBuffer().isEmpty();
-  }
-
-  /**
-   * Return true if the apply rollback buffers are all empty.
-   */
-  public boolean isApplyRollbackEmpty() {
-    return rollback.getBuffer().isEmpty()
-        && rollbackForeignKeys.getBuffer().isEmpty();
-  }
-
-  /**
-   * Return true the drop buffers are empty.
-   */
-  public boolean isDropEmpty() {
-    return drop.getBuffer().isEmpty() && dropHistory.getBuffer().isEmpty();
+        && applyHistory.getBuffer().isEmpty()
+        && applyDropDependencies.getBuffer().isEmpty();
   }
 
   /**
@@ -102,6 +72,13 @@ public class DdlWrite {
     return apply;
   }
 
+  /**
+   * Return the buffer that executes early to drop dependencies like views etc.
+   */
+  public DdlBuffer applyDropDependencies() {
+    return applyDropDependencies;
+  }
+
   /**
    * Return the buffer that APPLY DDL is written to for foreign keys and their associated indexes.
    * <p>
@@ -120,41 +97,17 @@ public class DdlWrite {
   }
 
   /**
-   * Return the buffer that ROLLBACK DDL is written to for foreign keys and associated indexes.
+   * Return the buffer used for the 'drop all DDL' for dropping foreign keys and associated indexes.
    */
-  public DdlBuffer rollbackForeignKeys() {
-    return rollbackForeignKeys;
+  public DdlBuffer dropAllForeignKeys() {
+    return dropAllForeignKeys;
   }
 
   /**
-   * Return the buffer that ROLLBACK DDL is written to which is considered safe to run when
-   * apply changes fail to execute. This will reverse the apply changes typically dropping
-   * newly created tables, foreign keys etc.
-   * <p>
-   * When apply changes are made against DB's that support transactional DDL you could argue
-   * that these rollback statements are not necessary.
-   * <p>
-   * Note that statements added to this rollback buffer are executed after foreign key rollback
-   * has been executed.
+   * Return the buffer used for the 'drop all DDL' to drop tables, views and history triggers etc.
    */
-  public DdlBuffer rollback() {
-    return rollback;
+  public DdlBuffer dropAll() {
+    return dropAll;
   }
 
-  /**
-   * Return the buffer that destructive changes are written to. This is typically drop table and
-   * drop column.
-   */
-  public DdlBuffer drop() {
-    return drop;
-  }
-
-  /**
-   * Return the buffer that is used when history is no longer required on a table or specific columns.
-   */
-  public DdlBuffer dropHistory() {
-    return dropHistory;
-  }
-
-
 }

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/BaseTableDdl.java

@@ -140,7 +140,7 @@ public class BaseTableDdl implements TableDdl {
 
     // add drop table to the rollback buffer - do this before
     // we drop the related sequence (if sequences are used)
-    dropTable(writer.rollback(), tableName);
+    dropTable(writer.dropAll(), tableName);
 
     if (useSequence) {
       String pkCol = pk.get(0).getName();
@@ -149,7 +149,7 @@ public class BaseTableDdl implements TableDdl {
 
     // add blank line for a bit of whitespace between tables
     apply.end();
-    writer.rollback().end();
+    writer.dropAll().end();
 
     writeAddForeignKeys(writer, createTable);
 
@@ -204,7 +204,7 @@ public class BaseTableDdl implements TableDdl {
           .append(platformDdl.alterTableAddUniqueConstraint(tableName, uqName, columnNames))
           .endOfStatement();
 
-      write.rollbackForeignKeys()
+      write.dropAllForeignKeys()
           .append(platformDdl.dropIndex(uqName, tableName))
           .endOfStatement();
     }
@@ -225,7 +225,7 @@ public class BaseTableDdl implements TableDdl {
     String createSeq = platformDdl.createSequence(seqName, initial, allocate);
     if (createSeq != null) {
       writer.apply().append(createSeq).newLine();
-      writer.rollback().append(platformDdl.dropSequence(seqName)).endOfStatement();
+      writer.dropAll().append(platformDdl.dropSequence(seqName)).endOfStatement();
     }
   }
 
@@ -295,15 +295,15 @@ public class BaseTableDdl implements TableDdl {
 
     fkeyBuffer.end();
 
-    write.rollbackForeignKeys()
+    write.dropAllForeignKeys()
         .append(platformDdl.alterTableDropForeignKey(tableName, fkName)).endOfStatement();
 
     if (indexName != null) {
-      write.rollbackForeignKeys()
+      write.dropAllForeignKeys()
           .append(platformDdl.dropIndex(indexName, tableName)).endOfStatement();
     }
 
-    write.rollbackForeignKeys().end();
+    write.dropAllForeignKeys().end();
 
   }
 
@@ -471,7 +471,7 @@ public class BaseTableDdl implements TableDdl {
         .append(platformDdl.createIndex(createIndex.getIndexName(), createIndex.getTableName(), cols))
         .endOfStatement();
 
-    writer.rollback()
+    writer.dropAll()
         .append(platformDdl.dropIndex(createIndex.getIndexName(), createIndex.getTableName()))
         .endOfStatement();
   }
@@ -520,7 +520,6 @@ public class BaseTableDdl implements TableDdl {
     List<Column> columns = addColumn.getColumn();
     for (Column column : columns) {
       alterTableAddColumn(writer.apply(), tableName, column, false);
-      alterTableDropColumn(writer.rollback(), tableName, column.getName());
     }
 
     if (isTrue(addColumn.isWithHistory())) {
@@ -529,13 +528,11 @@ public class BaseTableDdl implements TableDdl {
       for (Column column : columns) {
         regenerateHistoryTriggers(tableName, HistoryTableUpdate.Change.ADD, column.getName());
         alterTableAddColumn(writer.apply(), historyTable, column, true);
-        alterTableDropColumn(writer.rollback(), historyTable, column.getName());
       }
     }
 
     // add a bit of whitespace
     writer.apply().end();
-    writer.rollback().end();
   }
 
   /**
@@ -544,7 +541,7 @@ public class BaseTableDdl implements TableDdl {
   @Override
   public void generate(DdlWrite writer, DropTable dropTable) throws IOException {
 
-    dropTable(writer.drop(), dropTable.getName());
+    dropTable(writer.apply(), dropTable.getName());
   }
 
   /**
@@ -555,14 +552,14 @@ public class BaseTableDdl implements TableDdl {
 
     String tableName = dropColumn.getTableName();
 
-    alterTableDropColumn(writer.drop(), tableName, dropColumn.getColumnName());
+    alterTableDropColumn(writer.apply(), tableName, dropColumn.getColumnName());
     if (isTrue(dropColumn.isWithHistory())) {
       // also drop from the history table
       regenerateHistoryTriggers(tableName, HistoryTableUpdate.Change.DROP, dropColumn.getColumnName());
-      alterTableDropColumn(writer.drop(), historyTable(tableName), dropColumn.getColumnName());
+      alterTableDropColumn(writer.apply(), historyTable(tableName), dropColumn.getColumnName());
     }
 
-    writer.drop().end();
+    writer.apply().end();
   }
 
   /**
@@ -642,21 +639,6 @@ public class BaseTableDdl implements TableDdl {
     if (hasValue(ddl)) {
       writer.apply().append(ddl).endOfStatement();
 
-      // reverse and generate the rollback statement
-      String currentType = alter.getCurrentType();
-      String type = alter.getType();
-      Boolean currentNotnull = alter.isCurrentNotnull();
-      Boolean notnull = alter.isNotnull();
-
-      alter.setCurrentType(type);
-      alter.setType(currentType);
-      alter.setNotnull(currentNotnull);
-      alter.setCurrentNotnull(notnull);
-
-      // write the rollback
-      ddl = platformDdl.alterColumnBaseAttributes(alter);
-      writer.rollback().append(ddl).endOfStatement();
-
       if (isTrue(alter.isWithHistory()) && alter.getType() != null) {
         // mysql and sql server column type change allowing nulls in the history table column
         AlterColumn alterHistoryColumn = new AlterColumn();
@@ -667,11 +649,6 @@ public class BaseTableDdl implements TableDdl {
 
         // write the apply to history table
         writer.apply().append(histColumnDdl).endOfStatement();
-
-        // write the rollback from history table
-        alterHistoryColumn.setType(currentType);
-        histColumnDdl = platformDdl.alterColumnBaseAttributes(alterHistoryColumn);
-        writer.rollback().append(histColumnDdl).endOfStatement();
       }
     }
   }
@@ -689,8 +666,6 @@ public class BaseTableDdl implements TableDdl {
     String ddl = platformDdl.alterColumnNotnull(alter.getTableName(), alter.getColumnName(), alter.isNotnull());
     if (hasValue(ddl)) {
       writer.apply().append(ddl).endOfStatement();
-      ddl = platformDdl.alterColumnNotnull(alter.getTableName(), alter.getColumnName(), alter.isCurrentNotnull());
-      writer.rollback().append(ddl).endOfStatement();
     }
   }
 
@@ -699,14 +674,10 @@ public class BaseTableDdl implements TableDdl {
     String ddl = platformDdl.alterColumnType(alter.getTableName(), alter.getColumnName(), alter.getType());
     if (hasValue(ddl)) {
       writer.apply().append(ddl).endOfStatement();
-      ddl = platformDdl.alterColumnType(alter.getTableName(), alter.getColumnName(), alter.getCurrentType());
-      writer.rollback().append(ddl).endOfStatement();
       if (isTrue(alter.isWithHistory())) {
         // apply same type change to matching column in the history table
         ddl = platformDdl.alterColumnType(historyTable(alter.getTableName()), alter.getColumnName(), alter.getType());
         writer.apply().append(ddl).endOfStatement();
-        ddl = platformDdl.alterColumnType(historyTable(alter.getTableName()), alter.getColumnName(), alter.getCurrentType());
-        writer.rollback().append(ddl).endOfStatement();
       }
     }
   }
@@ -762,7 +733,7 @@ public class BaseTableDdl implements TableDdl {
         .append(platformDdl.alterTableAddUniqueConstraint(alter.getTableName(), uqName, cols))
         .endOfStatement();
 
-    writer.rollbackForeignKeys()
+    writer.dropAllForeignKeys()
         .append(platformDdl.dropIndex(uqName, alter.getTableName()))
         .endOfStatement();
   }

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/DbTriggerBasedHistoryDdl.java

@@ -10,7 +10,6 @@ import com.avaje.ebean.dbmigration.model.MColumn;
 import com.avaje.ebean.dbmigration.model.MTable;
 
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 
@@ -45,21 +44,43 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
     this.historySuffix = serverConfig.getHistoryTableSuffix();
     this.constraintNaming = serverConfig.getConstraintNaming();
 
-    this.sysPeriodStart = sysPeriod+"_start";
-    this.sysPeriodEnd = sysPeriod+"_end";
+    this.sysPeriodStart = sysPeriod + "_start";
+    this.sysPeriodEnd = sysPeriod + "_end";
   }
 
   @Override
-  public void regenerateHistoryTriggers(DdlWrite writer, HistoryTableUpdate update) throws IOException {
+  public void updateTriggers(DdlWrite writer, HistoryTableUpdate update) throws IOException {
 
     MTable table = writer.getTable(update.getBaseTable());
     if (table == null) {
-      throw new IllegalStateException("MTable "+update.getBaseTable()+" not found in writer? (required for history DDL)");
+      throw new IllegalStateException("MTable " + update.getBaseTable() + " not found in writer? (required for history DDL)");
     }
-    regenerateHistoryTriggers(writer, table, update);
+    updateTriggers(writer, table, update);
   }
 
-  protected abstract void regenerateHistoryTriggers(DdlWrite writer, MTable table, HistoryTableUpdate update) throws IOException;
+  /**
+   * Replace the existing triggers/stored procedures/views for history table support given the included columns.
+   */
+  protected abstract void updateHistoryTriggers(DbTriggerUpdate triggerUpdate) throws IOException;
+
+  /**
+   * Process the HistoryTableUpdate which can result in changes to the apply, rollback
+   * and drop scripts.
+   */
+  protected void updateTriggers(DdlWrite writer, MTable table, HistoryTableUpdate update) throws IOException {
+
+    writer.applyHistory().append("-- changes: ").append(update.description()).newLine();
+
+    updateHistoryTriggers(createDbTriggerUpdate(writer, table));
+  }
+
+  protected DbTriggerUpdate createDbTriggerUpdate(DdlWrite writer, MTable table) {
+
+    List<String> columns = columnNamesForApply(table);
+    String baseTableName = table.getName();
+    String historyTableName = historyTableName(baseTableName);
+    return new DbTriggerUpdate(baseTableName, historyTableName, writer, columns);
+  }
 
   @Override
   public void dropHistoryTable(DdlWrite writer, DropHistoryTable dropHistoryTable) throws IOException {
@@ -67,18 +88,17 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
     String baseTable = dropHistoryTable.getBaseTable();
 
     // drop in appropriate order
-    dropTriggers(writer.dropHistory(), baseTable);
-    dropHistoryTableEtc(writer.dropHistory(), baseTable);
+    dropTriggers(writer.applyDropDependencies(), baseTable);
+    dropHistoryTableEtc(writer.applyDropDependencies(), baseTable);
   }
 
-
   @Override
   public void addHistoryTable(DdlWrite writer, AddHistoryTable addHistoryTable) throws IOException {
 
     String baseTable = addHistoryTable.getBaseTable();
     MTable table = writer.getTable(baseTable);
     if (table == null) {
-      throw new IllegalStateException("MTable "+baseTable+" not found in writer? (required for history DDL)");
+      throw new IllegalStateException("MTable " + baseTable + " not found in writer? (required for history DDL)");
     }
 
     createWithHistory(writer, table);
@@ -90,12 +110,11 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
     String baseTable = table.getName();
     String whenCreatedColumn = table.getWhenCreatedColumn();
 
-    // rollback changes in appropriate order
-    dropTriggers(writer.rollback(), baseTable);
-    dropHistoryTableEtc(writer.rollback(), baseTable);
+    dropTriggers(writer.dropAll(), baseTable);
+    dropHistoryTableEtc(writer.dropAll(), baseTable);
 
     addHistoryTable(writer, table, whenCreatedColumn);
-    addStoredFunction(writer, table, null);
+    createStoredFunction(writer, table);
     createTriggers(writer, table);
   }
 
@@ -103,7 +122,7 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
 
   protected abstract void dropTriggers(DdlBuffer buffer, String baseTable) throws IOException;
 
-  protected void addStoredFunction(DdlWrite writer, MTable table, HistoryTableUpdate update) throws IOException {
+  protected void createStoredFunction(DdlWrite writer, MTable table) throws IOException {
     // do nothing
   }
 
@@ -158,7 +177,7 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
 
     apply.append("create table ").append(table.getName()).append(historySuffix).append("(").newLine();
 
-    Collection<MColumn> cols = table.getColumns().values();
+    Collection<MColumn> cols = table.allColumns();
     for (MColumn column : cols) {
       if (!column.isDraftOnly()) {
         writeColumnDefinition(apply, column.getName(), column.getType());
@@ -191,6 +210,26 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
         .endOfStatement().end();
   }
 
+  /**
+   * Create or replace the with_history view with explicit columns.
+   */
+  protected void createWithHistoryView(DbTriggerUpdate update) throws IOException {
+
+    DdlBuffer apply = update.historyBuffer();
+    apply.append("create or replace view ").append(update.getBaseTable()).append(viewSuffix).append(" as select ");
+    appendColumnNames(apply, update.getColumns(), "");
+    appendSysPeriodColumns(apply, ", ");
+    apply.append(" from ").append(update.getBaseTable()).append(" union all select ");
+    appendColumnNames(apply, update.getColumns(), "");
+    appendSysPeriodColumns(apply, ", ");
+    apply.append(" from ").append(update.getHistoryTable()).endOfStatement().end();
+  }
+
+  protected void appendSysPeriodColumns(DdlBuffer apply, String prefix) throws IOException {
+    appendColumnName(apply, prefix, sysPeriodStart);
+    appendColumnName(apply, prefix, sysPeriodEnd);
+  }
+
   protected void dropHistoryTableEtc(DdlBuffer buffer, String baseTableName) throws IOException {
 
     buffer.append("drop view ").append(baseTableName).append(viewSuffix).endOfStatement();
@@ -203,8 +242,6 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
     buffer.append("alter table ").append(baseTableName).append(" drop column ").append(sysPeriodEnd).endOfStatement();
   }
 
-  //protected abstract void addFunction(DdlBuffer apply, String procedureName, String historyTable, List<String> includedColumns) throws IOException;
-
   protected void appendInsertIntoHistory(DdlBuffer buffer, String historyTable, List<String> columns) throws IOException {
 
     buffer.append("    insert into ").append(historyTable).append(" (").append(sysPeriodStart).append(",").append(sysPeriodEnd).append(",");
@@ -216,7 +253,7 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
 
   protected void appendColumnNames(DdlBuffer buffer, List<String> columns, String columnPrefix) throws IOException {
 
-    for (int i=0; i< columns.size(); i++) {
+    for (int i = 0; i < columns.size(); i++) {
       if (i > 0) {
         buffer.append(", ");
       }
@@ -226,18 +263,26 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
   }
 
   /**
-   * Return the list of included columns in order.
+   * Append a single column to the buffer if it is not null.
    */
-  protected List<String> includedColumnNames(MTable table) throws IOException {
+  protected void appendColumnName(DdlBuffer buffer, String prefix, String columnName) throws IOException {
 
-    Collection<MColumn> columns = table.getColumns().values();
-    List<String> includedColumns = new ArrayList<String>(columns.size());
-
-    for (MColumn column : columns) {
-      if (column.isIncludeInHistory()) {
-        includedColumns.add(column.getName());
-      }
+    if (columnName != null) {
+      buffer.append(prefix).append(columnName);
     }
-    return includedColumns;
   }
+
+  /**
+   * Return the column names included in history for the apply script.
+   * <p>
+   * Note that dropped columns are actually still included at this point as they are going
+   * to be removed from the history handling when the drop script runs that also deletes
+   * the column.
+   * </p>
+   */
+  protected List<String> columnNamesForApply(MTable table) {
+
+    return table.allHistoryColumns(true);
+  }
+
 }

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/DbTriggerUpdate.java

@@ -0,0 +1,63 @@
+package com.avaje.ebean.dbmigration.ddlgeneration.platform;
+
+import com.avaje.ebean.dbmigration.ddlgeneration.DdlBuffer;
+import com.avaje.ebean.dbmigration.ddlgeneration.DdlWrite;
+
+import java.util.List;
+
+/**
+ * DB trigger update when a change occurs on a table with history.
+ */
+public class DbTriggerUpdate {
+
+  private final String baseTableName;
+
+  private final String historyTableName;
+
+  private final DdlWrite writer;
+
+  private final List<String> columns;
+
+  public DbTriggerUpdate(String baseTableName, String historyTableName, DdlWrite writer, List<String> columns) {
+    this.baseTableName = baseTableName;
+    this.historyTableName = historyTableName;
+    this.writer = writer;
+    this.columns = columns;
+  }
+
+  /**
+   * Return the appropriate buffer for the current mode.
+   */
+  public DdlBuffer historyBuffer() {
+    return writer.applyHistory();
+  }
+
+  /**
+   * Return the appropriate drop dependency buffer for the current mode.
+   */
+  public DdlBuffer dropDependencyBuffer() {
+    return writer.applyDropDependencies();
+  }
+
+  /**
+   * Return the base table name.
+   */
+  public String getBaseTable() {
+    return baseTableName;
+  }
+
+  /**
+   * Return the history table name.
+   */
+  public String getHistoryTable() {
+    return historyTableName;
+  }
+
+  /**
+   * Return the included columns.
+   */
+  public List<String> getColumns() {
+    return columns;
+  }
+
+}

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/H2HistoryDdl.java

@@ -6,7 +6,6 @@ import com.avaje.ebean.dbmigration.ddlgeneration.DdlWrite;
 import com.avaje.ebean.dbmigration.model.MTable;
 
 import java.io.IOException;
-import java.util.List;
 
 /**
  * H2 history support using DB triggers to maintain a history table.
@@ -28,40 +27,20 @@ public class H2HistoryDdl extends DbTriggerBasedHistoryDdl {
   protected void createTriggers(DdlWrite writer, MTable table) throws IOException {
 
     String baseTableName = table.getName();
-    String historyTableName = historyTableName(baseTableName);
-    List<String> includedColumns = includedColumnNames(table);
-
     DdlBuffer apply = writer.applyHistory();
 
-    addCreateTrigger(apply, updateTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
+    addCreateTrigger(apply, updateTriggerName(baseTableName), baseTableName);
   }
 
   @Override
-  protected void regenerateHistoryTriggers(DdlWrite writer, MTable table, HistoryTableUpdate update) throws IOException {
+  protected void updateHistoryTriggers(DbTriggerUpdate update) throws IOException {
 
-    String baseTableName = table.getName();
-    String historyTableName = historyTableName(baseTableName);
-    List<String> includedColumns = includedColumnNames(table);
-
-    DdlBuffer apply = writer.applyHistory();
-
-    apply.append("-- Regenerated ").newLine();
-    apply.append("-- changes: ").append(update.description()).newLine();
-
-    dropTriggers(apply, baseTableName);
-    addCreateTrigger(apply, updateTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
-
-    // put a reverted version into the rollback buffer
-    update.toRevertedColumns(includedColumns);
-
-    DdlBuffer rollback = writer.rollback();
-    rollback.append("-- Revert regenerated ").newLine();
-    rollback.append("-- revert changes: ").append(update.description()).newLine();
-    dropTriggers(rollback, baseTableName);
-    addCreateTrigger(rollback, updateTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
+    DdlBuffer buffer = update.historyBuffer();
+    dropTriggers(buffer, update.getBaseTable());
+    addCreateTrigger(buffer, updateTriggerName(update.getBaseTable()), update.getBaseTable());
   }
 
-  private void addCreateTrigger(DdlBuffer apply, String triggerName, String baseTable, String historyTable, List<String> includedColumns) throws IOException {
+  private void addCreateTrigger(DdlBuffer apply, String triggerName, String baseTable) throws IOException {
 
     // Note that this does not take into account the historyTable name (excepts _history suffix) and
     // does not take into account excluded columns (all columns included in history)

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/HistoryTableUpdate.java

@@ -10,7 +10,6 @@ import java.util.List;
  */
 public class HistoryTableUpdate {
 
-
   /**
    * Column change type.
    */
@@ -21,35 +20,25 @@ public class HistoryTableUpdate {
     EXCLUDE
   }
 
-  public static class Column {
+  private static class Column {
+
+    final Change change;
+
+    final String column;
 
-    public final Change change;
-    public final String column;
     public Column(Change change, String column) {
       this.change = change;
       this.column = column;
     }
 
+    public String toString() {
+      return description();
+    }
+
     public String description() {
       return change.name().toLowerCase()+" "+column;
     }
 
-    public void apply(List<String> includedColumns) {
-      switch (change) {
-        case ADD:
-        case INCLUDE: {
-          includedColumns.remove(column);
-          break;
-        }
-        case DROP:
-        case EXCLUDE: {
-          includedColumns.add(column);
-          break;
-        }
-        default:
-          throw new IllegalStateException("Unexpected change "+change);
-      }
-    }
   }
 
   private final String baseTable;
@@ -65,27 +54,12 @@ public class HistoryTableUpdate {
 
   /**
    * Return a description of the changes that cause the history trigger/function
-   * to be regenerated (added, dropped, included or excluded columns).
+   * to be regenerated (added, included, excluded and dropped columns).
    */
   public String description() {
-    StringBuilder sb = new StringBuilder(90);
-    for (int i = 0; i < columnChanges.size(); i++) {
-      if (i > 0) {
-        sb.append(", ");
-      }
-      sb.append(columnChanges.get(i).description());
-    }
-    return sb.toString();
+    return columnChanges.toString();
   }
 
-  public void toRevertedColumns(List<String> includedColumns) {
-
-    for (Column columnChange : columnChanges) {
-      columnChange.apply(includedColumns);
-    }
-  }
-
-
   /**
    * Add a comment for column added, dropped, included or excluded.
    */
@@ -100,10 +74,4 @@ public class HistoryTableUpdate {
     return baseTable;
   }
 
-  /**
-   * Return the comments.
-   */
-  public List<Column> getColumnChanges() {
-    return columnChanges;
-  }
 }

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/MySqlHistoryDdl.java

@@ -5,7 +5,6 @@ import com.avaje.ebean.dbmigration.ddlgeneration.DdlWrite;
 import com.avaje.ebean.dbmigration.model.MTable;
 
 import java.io.IOException;
-import java.util.List;
 
 /**
  * MySql history support using DB triggers to maintain a history table.
@@ -26,67 +25,46 @@ public class MySqlHistoryDdl extends DbTriggerBasedHistoryDdl {
   @Override
   protected void createTriggers(DdlWrite writer, MTable table) throws IOException {
 
-    String baseTableName = table.getName();
-    String historyTableName = historyTableName(baseTableName);
-    List<String> includedColumns = includedColumnNames(table);
+    DbTriggerUpdate update = createDbTriggerUpdate(writer, table);
 
-    DdlBuffer apply = writer.applyHistory();
-
-    addBeforeUpdate(apply, updateTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
-    addBeforeDelete(apply, deleteTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
+    addBeforeUpdate(updateTriggerName(update.getBaseTable()), update);
+    addBeforeDelete(deleteTriggerName(update.getBaseTable()), update);
   }
 
   @Override
-  protected void regenerateHistoryTriggers(DdlWrite writer, MTable table, HistoryTableUpdate update) throws IOException {
+  protected void updateHistoryTriggers(DbTriggerUpdate update) throws IOException {
 
-    String baseTableName = table.getName();
-    String historyTableName = historyTableName(baseTableName);
-    List<String> includedColumns = includedColumnNames(table);
+    DdlBuffer buffer = update.historyBuffer();
+    String baseTable = update.getBaseTable();
 
-    DdlBuffer apply = writer.applyHistory();
-
-    apply.append("-- Regenerated ").newLine();
-    apply.append("-- changes: ").append(update.description()).newLine();
-    // lock the base table while we drop and recreate the triggers
-    apply.append("lock tables ").append(baseTableName).append(" write").endOfStatement();
-    dropTriggers(apply, baseTableName);
-    addBeforeUpdate(apply, updateTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
-    addBeforeDelete(apply, deleteTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
-    apply.append("unlock tables").endOfStatement();
-
-    // put a reverted version into the rollback buffer
-    update.toRevertedColumns(includedColumns);
-
-    DdlBuffer rollback = writer.rollback();
-    rollback.append("-- Revert regenerated ").newLine();
-    rollback.append("-- revert changes: ").append(update.description()).newLine();
-    // lock the base table while we drop and recreate the triggers
-    rollback.append("lock tables ").append(baseTableName).append(" write").endOfStatement();
-    dropTriggers(rollback, baseTableName);
-    addBeforeUpdate(rollback, updateTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
-    addBeforeDelete(rollback, deleteTriggerName(baseTableName), baseTableName, historyTableName, includedColumns);
-    rollback.append("unlock tables").endOfStatement();
+    buffer.append("lock tables ").append(baseTable).append(" write").endOfStatement();
+    dropTriggers(buffer, baseTable);
+    addBeforeUpdate(updateTriggerName(baseTable), update);
+    addBeforeDelete(deleteTriggerName(baseTable), update);
+    buffer.append("unlock tables").endOfStatement();
   }
 
-  private void addBeforeUpdate(DdlBuffer apply, String triggerName, String baseTable, String historyTable, List<String> includedColumns) throws IOException {
+  private void addBeforeUpdate(String triggerName, DbTriggerUpdate update) throws IOException {
 
+    DdlBuffer apply = update.historyBuffer();
     apply
         .append("delimiter $$").newLine()
-        .append("create trigger ").append(triggerName).append(" before update on ").append(baseTable)
+        .append("create trigger ").append(triggerName).append(" before update on ").append(update.getBaseTable())
         .append(" for each row begin").newLine();
-    appendInsertIntoHistory(apply, historyTable, includedColumns);
+    appendInsertIntoHistory(apply, update.getHistoryTable(), update.getColumns());
     apply
         .append("    set NEW.").append(sysPeriod).append("_start = now(6)").endOfStatement()
         .append("end$$").newLine();
   }
 
-  private void addBeforeDelete(DdlBuffer apply, String triggerName, String baseTable, String historyTable, List<String> includedColumns) throws IOException {
+  private void addBeforeDelete(String triggerName, DbTriggerUpdate update) throws IOException {
 
+    DdlBuffer apply = update.historyBuffer();
     apply
         .append("delimiter $$").newLine()
-        .append("create trigger ").append(triggerName).append(" before delete on ").append(baseTable)
+        .append("create trigger ").append(triggerName).append(" before delete on ").append(update.getBaseTable())
         .append(" for each row begin").newLine();
-    appendInsertIntoHistory(apply, historyTable, includedColumns);
+    appendInsertIntoHistory(apply, update.getHistoryTable(), update.getColumns());
     apply.append("end$$").newLine();
   }
 

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/NoHistorySupportDdl.java

@@ -35,7 +35,7 @@ public class NoHistorySupportDdl implements PlatformHistoryDdl {
   }
 
   @Override
-  public void regenerateHistoryTriggers(DdlWrite write, HistoryTableUpdate update) {
+  public void updateTriggers(DdlWrite write, HistoryTableUpdate update) {
     // does nothing
   }
 }

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/PlatformDdl.java

@@ -200,7 +200,7 @@ public class PlatformDdl {
    * Regenerate the history triggers (or function) due to a column being added/dropped/excluded or included.
    */
   public void regenerateHistoryTriggers(DdlWrite write, HistoryTableUpdate update) throws IOException {
-    historyDdl.regenerateHistoryTriggers(write, update);
+    historyDdl.updateTriggers(write, update);
   }
 
   /**

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/PlatformHistoryDdl.java

@@ -36,5 +36,5 @@ public interface PlatformHistoryDdl {
   /**
    * Regenerate the history triggers/stored function due to column added/dropped/included or excluded.
    */
-  void regenerateHistoryTriggers(DdlWrite write, HistoryTableUpdate baseTable) throws IOException;
+  void updateTriggers(DdlWrite write, HistoryTableUpdate baseTable) throws IOException;
 }

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/PostgresHistoryDdl.java

@@ -45,6 +45,11 @@ public class PostgresHistoryDdl extends DbTriggerBasedHistoryDdl {
     }
   }
 
+  @Override
+  protected void appendSysPeriodColumns(DdlBuffer apply, String prefix) throws IOException {
+    appendColumnName(apply, prefix, sysPeriod);
+  }
+
   @Override
   protected void dropSysPeriodColumns(DdlBuffer buffer, String baseTableName) throws IOException {
     buffer.append("alter table ").append(baseTableName).append(" drop column ").append(sysPeriod).endOfStatement();
@@ -72,7 +77,7 @@ public class PostgresHistoryDdl extends DbTriggerBasedHistoryDdl {
     buffer.end();
   }
 
-  protected void addFunction(DdlBuffer apply, String procedureName, String historyTable, List<String> includedColumns) throws IOException {
+  protected void createOrReplaceFunction(DdlBuffer apply, String procedureName, String historyTable, List<String> includedColumns) throws IOException {
     apply
         .append("create or replace function ").append(procedureName).append("() returns trigger as $$").newLine()
         .append("begin").newLine();
@@ -96,40 +101,36 @@ public class PostgresHistoryDdl extends DbTriggerBasedHistoryDdl {
   }
 
   @Override
-  protected void regenerateHistoryTriggers(DdlWrite writer, MTable table, HistoryTableUpdate update) throws IOException {
-
-    // just replace the stored function with 'create or replace'
-    addStoredFunction(writer, table, update);
-  }
-
-  @Override
-  protected void addStoredFunction(DdlWrite writer, MTable table, HistoryTableUpdate update) throws IOException {
+  protected void createStoredFunction(DdlWrite writer, MTable table) throws IOException {
 
     String procedureName = procedureName(table.getName());
     String historyTable = historyTableName(table.getName());
 
-    List<String> includedColumns = includedColumnNames(table);
+    List<String> columnNames = columnNamesForApply(table);
+    createOrReplaceFunction(writer.applyHistory(), procedureName, historyTable, columnNames);
+  }
 
-    DdlBuffer apply = writer.applyHistory();
+  @Override
+  protected void updateHistoryTriggers(DbTriggerUpdate update) throws IOException {
 
-    if (update != null) {
-      apply.append("-- Regenerated ").append(procedureName).newLine();
-      apply.append("-- changes: ").append(update.description()).newLine();
-    }
+    String procedureName = procedureName(update.getBaseTable());
 
-    addFunction(apply, procedureName, historyTable, includedColumns);
+    recreateHistoryView(update);
+    createOrReplaceFunction(update.historyBuffer(), procedureName, update.getHistoryTable(), update.getColumns());
+  }
 
+  /**
+   * For postgres we need to drop and recreate the view. Well, we could add columns to the end of the view
+   * but otherwise we need to drop and create it.
+   */
+  private void recreateHistoryView(DbTriggerUpdate update) throws IOException {
 
-    if (update != null) {
-      // put a reverted version into the rollback buffer
-      update.toRevertedColumns(includedColumns);
+    DdlBuffer buffer = update.dropDependencyBuffer();
+    // we need to drop the view early/first before any changes to the tables etc
+    buffer.append("drop view if exists ").append(update.getBaseTable()).append(viewSuffix).endOfStatement();
 
-      DdlBuffer rollback = writer.rollback();
-      rollback.append("-- Revert regenerated ").append(procedureName).newLine();
-      rollback.append("-- revert changes: ").append(update.description()).newLine();
-
-      addFunction(rollback, procedureName, historyTable, includedColumns);
-    }
+    // recreate the view with specific columns specified (the columns generally are not dropped until later)
+    createWithHistoryView(update);
   }
 
   @Override

src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/util/PlatformTypeConverter.java

@@ -5,7 +5,7 @@ import com.avaje.ebean.config.dbplatform.DbTypeMap;
 
 /**
  * Converts a logical column definition into platform specific one.
- *
+ * <p>
  * This translates standard sql types into platform specific ones.
  */
 public class PlatformTypeConverter {
@@ -44,20 +44,21 @@ public class PlatformTypeConverter {
       return columnDefinition;
     }
 
-    String type = columnDefinition.substring(0,open);
+    String suffix = close + 1 < columnDefinition.length() ? columnDefinition.substring(close + 1) : "";
+    String type = columnDefinition.substring(0, open);
     try {
       DbType dbType = platformTypes.lookup(type);
-      int comma = columnDefinition.indexOf(',',open);
+      int comma = columnDefinition.indexOf(',', open);
       if (comma > -1) {
         // scale and precision - decimal(10,4)
-        int scale = Integer.parseInt(columnDefinition.substring(open+1, comma));
-        int precision = Integer.parseInt(columnDefinition.substring(comma+1, close));
-        return  dbType.renderType(scale,precision);
+        int scale = Integer.parseInt(columnDefinition.substring(open + 1, comma));
+        int precision = Integer.parseInt(columnDefinition.substring(comma + 1, close));
+        return dbType.renderType(scale, precision) + suffix;
 
       } else {
         // scale - varchar(10)
-        int scale = Integer.parseInt(columnDefinition.substring(open+1, close));
-        return  dbType.renderType(scale,0);
+        int scale = Integer.parseInt(columnDefinition.substring(open + 1, close));
+        return dbType.renderType(scale, 0) + suffix;
       }
 
     } catch (IllegalArgumentException e) {
@@ -73,7 +74,7 @@ public class PlatformTypeConverter {
 
     try {
       DbType dbType = platformTypes.lookup(columnDefinition);
-      return  dbType.renderType(0,0);
+      return dbType.renderType(0, 0);
 
     } catch (IllegalArgumentException e) {
       // assume already platform specific, leave as is

src/main/java/com/avaje/ebean/dbmigration/migration/ChangeSet.java

@@ -27,6 +27,8 @@ import javax.xml.bind.annotation.XmlType;
  *         </choice>
  *       </sequence>
  *       <attribute name="type" use="required" type="{http://ebean-orm.github.io/xml/ns/dbmigration}changeSetType" />
+ *       <attribute name="dropsFor" type="{http://www.w3.org/2001/XMLSchema}string" />
+ *       <attribute name="suppressDropsForever" type="{http://www.w3.org/2001/XMLSchema}boolean" />
  *       <attribute name="generated" type="{http://www.w3.org/2001/XMLSchema}boolean" />
  *       <attribute name="author" type="{http://www.w3.org/2001/XMLSchema}string" />
  *       <attribute name="comment" type="{http://www.w3.org/2001/XMLSchema}string" />
@@ -62,6 +64,10 @@ public class ChangeSet {
     protected List<Object> changeSetChildren;
     @XmlAttribute(name = "type", required = true)
     protected ChangeSetType type;
+    @XmlAttribute(name = "dropsFor")
+    protected String dropsFor;
+    @XmlAttribute(name = "suppressDropsForever")
+    protected Boolean suppressDropsForever;
     @XmlAttribute(name = "generated")
     protected Boolean generated;
     @XmlAttribute(name = "author")
@@ -134,6 +140,54 @@ public class ChangeSet {
         this.type = value;
     }
 
+    /**
+     * Gets the value of the dropsFor property.
+     * 
+     * @return
+     *     possible object is
+     *     {@link String }
+     *     
+     */
+    public String getDropsFor() {
+        return dropsFor;
+    }
+
+    /**
+     * Sets the value of the dropsFor property.
+     * 
+     * @param value
+     *     allowed object is
+     *     {@link String }
+     *     
+     */
+    public void setDropsFor(String value) {
+        this.dropsFor = value;
+    }
+
+    /**
+     * Gets the value of the suppressDropsForever property.
+     * 
+     * @return
+     *     possible object is
+     *     {@link Boolean }
+     *     
+     */
+    public Boolean isSuppressDropsForever() {
+        return suppressDropsForever;
+    }
+
+    /**
+     * Sets the value of the suppressDropsForever property.
+     * 
+     * @param value
+     *     allowed object is
+     *     {@link Boolean }
+     *     
+     */
+    public void setSuppressDropsForever(Boolean value) {
+        this.suppressDropsForever = value;
+    }
+
     /**
      * Gets the value of the generated property.
      * 

src/main/java/com/avaje/ebean/dbmigration/migration/ChangeSetType.java

@@ -15,7 +15,7 @@ import javax.xml.bind.annotation.XmlType;
  * <simpleType name="changeSetType">
  *   <restriction base="{http://www.w3.org/2001/XMLSchema}string">
  *     <enumeration value="apply"/>
- *     <enumeration value="drop"/>
+ *     <enumeration value="pendingDrops"/>
  *     <enumeration value="baseline"/>
  *   </restriction>
  * </simpleType>
@@ -28,8 +28,8 @@ public enum ChangeSetType {
 
     @XmlEnumValue("apply")
     APPLY("apply"),
-    @XmlEnumValue("drop")
-    DROP("drop"),
+    @XmlEnumValue("pendingDrops")
+    PENDING_DROPS("pendingDrops"),
     @XmlEnumValue("baseline")
     BASELINE("baseline");
     private final String value;

src/main/java/com/avaje/ebean/dbmigration/migration/CreateTable.java

@@ -30,6 +30,7 @@ import javax.xml.bind.annotation.XmlType;
  *       <attGroup ref="{http://ebean-orm.github.io/xml/ns/dbmigration}tablespaceAttributes"/>
  *       <attribute name="name" use="required" type="{http://www.w3.org/2001/XMLSchema}string" />
  *       <attribute name="withHistory" type="{http://www.w3.org/2001/XMLSchema}boolean" />
+ *       <attribute name="draft" type="{http://www.w3.org/2001/XMLSchema}boolean" />
  *       <attribute name="identityType" type="{http://ebean-orm.github.io/xml/ns/dbmigration}identityType" />
  *       <attribute name="sequenceName" type="{http://www.w3.org/2001/XMLSchema}string" />
  *       <attribute name="sequenceInitial" type="{http://www.w3.org/2001/XMLSchema}positiveInteger" />
@@ -59,6 +60,8 @@ public class CreateTable {
     protected String name;
     @XmlAttribute(name = "withHistory")
     protected Boolean withHistory;
+    @XmlAttribute(name = "draft")
+    protected Boolean draft;
     @XmlAttribute(name = "identityType")
     protected IdentityType identityType;
     @XmlAttribute(name = "sequenceName")
@@ -213,6 +216,30 @@ public class CreateTable {
         this.withHistory = value;
     }
 
+    /**
+     * Gets the value of the draft property.
+     * 
+     * @return
+     *     possible object is
+     *     {@link Boolean }
+     *     
+     */
+    public Boolean isDraft() {
+        return draft;
+    }
+
+    /**
+     * Sets the value of the draft property.
+     * 
+     * @param value
+     *     allowed object is
+     *     {@link Boolean }
+     *     
+     */
+    public void setDraft(Boolean value) {
+        this.draft = value;
+    }
+
     /**
      * Gets the value of the identityType property.
      * 

src/main/java/com/avaje/ebean/dbmigration/model/CurrentModel.java

@@ -117,13 +117,13 @@ public class CurrentModel {
   /**
    * Return the 'Drop' DDL.
    */
-  public String getDropDdl() throws IOException {
+  public String getDropAllDdl() throws IOException {
 
     createDdl();
 
     StringBuilder ddl = new StringBuilder(2000);
-    ddl.append(write.rollbackForeignKeys().getBuffer());
-    ddl.append(write.rollback().getBuffer());
+    ddl.append(write.dropAllForeignKeys().getBuffer());
+    ddl.append(write.dropAll().getBuffer());
 
     return ddl.toString();
   }
@@ -159,12 +159,7 @@ public class CurrentModel {
     ModelDiff diff = new ModelDiff();
     diff.compareTo(model);
 
-    List<Object> applyChanges = diff.getApplyChanges();
-
-    // put the changes into a ChangeSet
-    ChangeSet applyChangeSet = new ChangeSet();
-    applyChangeSet.getChangeSetChildren().addAll(applyChanges);
-    return applyChangeSet;
+    return diff.getApplyChangeSet();
   }
 
 }

src/main/java/com/avaje/ebean/dbmigration/model/MColumn.java

@@ -283,7 +283,6 @@ public class MColumn {
   /**
    * Compare the column meta data and return true if there is a change that means
    * the history table column needs
-
    */
   public void compare(ModelDiff modelDiff, MTable table, MColumn newColumn) {
 

src/main/java/com/avaje/ebean/dbmigration/model/MTable.java

@@ -10,13 +10,14 @@ import com.avaje.ebean.dbmigration.migration.DropHistoryTable;
 import com.avaje.ebean.dbmigration.migration.DropTable;
 import com.avaje.ebean.dbmigration.migration.IdentityType;
 import com.avaje.ebean.dbmigration.migration.UniqueConstraint;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.math.BigInteger;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -38,6 +39,8 @@ import java.util.Set;
  */
 public class MTable {
 
+  private static final Logger logger = LoggerFactory.getLogger(MTable.class);
+
   /**
    * Table name.
    */
@@ -118,6 +121,8 @@ public class MTable {
    */
   private AddColumn addColumn;
 
+  private List<String> droppedColumns = new ArrayList<String>();
+
   /**
    * Create a copy of this table structure as a 'draft' table.
    *
@@ -126,14 +131,14 @@ public class MTable {
    */
   public MTable createDraftTable() {
 
-    draftTable = new MTable(name+"_draft");
+    draftTable = new MTable(name + "_draft");
     draftTable.draft = true;
     draftTable.whenCreatedColumn = whenCreatedColumn;
     // compoundKeys
     // compoundUniqueConstraints
     draftTable.identityType = identityType;
 
-    for (MColumn col: columns.values()) {
+    for (MColumn col : allColumns()) {
       draftTable.addColumn(col.copyForDraft());
     }
 
@@ -150,6 +155,7 @@ public class MTable {
     this.tablespace = createTable.getTablespace();
     this.indexTablespace = createTable.getIndexTablespace();
     this.withHistory = Boolean.TRUE.equals(createTable.isWithHistory());
+    this.draft = Boolean.TRUE.equals(createTable.isDraft());
     this.sequenceName = createTable.getSequenceName();
     this.sequenceInitial = toInt(createTable.getSequenceInitial());
     this.sequenceAllocate = toInt(createTable.getSequenceAllocate());
@@ -194,8 +200,11 @@ public class MTable {
     if (withHistory) {
       createTable.setWithHistory(Boolean.TRUE);
     }
+    if (draft) {
+      createTable.setDraft(Boolean.TRUE);
+    }
 
-    for (MColumn column : this.columns.values()) {
+    for (MColumn column : allColumns()) {
       // filter out draftOnly columns from the base table
       if (draft || !column.isDraftOnly()) {
         createTable.getColumn().add(column.createColumn());
@@ -244,26 +253,33 @@ public class MTable {
 
     addColumn = null;
 
-    Set<String> mappedColumns = new LinkedHashSet<String>();
+    Map<String, MColumn> newColumnMap = newTable.getColumns();
 
-    Collection<MColumn> newColumns = newTable.getColumns().values();
-    for (MColumn newColumn : newColumns) {
-      MColumn localColumn = columns.get(newColumn.getName());
+    // compare newColumns to existing columns (look for new and diff columns)
+    for (MColumn newColumn : newColumnMap.values()) {
+      MColumn localColumn = getColumn(newColumn.getName());
       if (localColumn == null) {
-        diffNewColumn(newColumn);
+        // can ignore if draftOnly column and non-draft table
+        if (!newColumn.isDraftOnly() || draft) {
+          diffNewColumn(newColumn);
+        }
       } else {
-        // note that if there are alter column changes in here then
-        // the table withHistory is taken into account
         localColumn.compare(modelDiff, this, newColumn);
-        mappedColumns.add(newColumn.getName());
       }
     }
 
-    Collection<MColumn> existingColumns = columns.values();
-    for (MColumn existingColumn : existingColumns) {
-      if (!mappedColumns.contains(existingColumn.getName())) {
-        diffDropColumn(modelDiff, existingColumn);
+    // compare existing columns (look for dropped columns)
+    int columnPosition = 0;
+    for (MColumn existingColumn : allColumns()) {
+      MColumn newColumn = newColumnMap.get(existingColumn.getName());
+      if (newColumn == null) {
+        diffDropColumn(modelDiff, existingColumn, columnPosition, newTable);
+      } else if (newColumn.isDraftOnly() && !draft) {
+        // effectively a drop column (draft only column on a non-draft table)
+        logger.trace("... drop column {} from table {} as now draftOnly", newColumn.getName(), name);
+        diffDropColumn(modelDiff, existingColumn, columnPosition, newTable);
       }
+      columnPosition++;
     }
 
     if (addColumn != null) {
@@ -287,7 +303,7 @@ public class MTable {
   public void apply(AlterColumn alterColumn) {
     checkTableName(alterColumn.getTableName());
     String columnName = alterColumn.getColumnName();
-    MColumn existingColumn = columns.get(columnName);
+    MColumn existingColumn = getColumn(columnName);
     if (existingColumn == null) {
       throw new IllegalStateException("Column [" + columnName + "] does not exist for AlterColumn change?");
     }
@@ -299,7 +315,10 @@ public class MTable {
    */
   public void apply(DropColumn dropColumn) {
     checkTableName(dropColumn.getTableName());
-    columns.remove(dropColumn.getColumnName());
+    MColumn removed = columns.remove(dropColumn.getColumnName());
+    if (removed == null) {
+      throw new IllegalStateException("Column [" + dropColumn.getColumnName() + "] does not exist for DropColumn change on table [" + dropColumn.getTableName() + "]?");
+    }
   }
 
   public String getName() {
@@ -313,10 +332,6 @@ public class MTable {
     return draft;
   }
 
-  public String getPkName() {
-    return pkName;
-  }
-
   public void setPkName(String pkName) {
     this.pkName = pkName;
   }
@@ -341,11 +356,43 @@ public class MTable {
     return withHistory;
   }
 
-  public void setWithHistory(boolean withHistory) {
+  public MTable setWithHistory(boolean withHistory) {
     this.withHistory = withHistory;
+    return this;
   }
 
-  public Map<String, MColumn> getColumns() {
+  public List<String> allHistoryColumns(boolean includeDropped) {
+
+    List<String> columnNames = new ArrayList<String>(columns.size());
+    for (MColumn column : columns.values()) {
+      if (column.isIncludeInHistory()) {
+        columnNames.add(column.getName());
+      }
+    }
+    if (includeDropped && !droppedColumns.isEmpty()) {
+      for (String droppedColumn : droppedColumns) {
+        columnNames.add(droppedColumn);
+      }
+    }
+    return columnNames;
+  }
+
+  /**
+   * Return all the columns (excluding columns marked as dropped).
+   */
+  public Collection<MColumn> allColumns() {
+
+    return columns.values();
+  }
+
+  /**
+   * Return the column by name.
+   */
+  public MColumn getColumn(String name) {
+    return columns.get(name);
+  }
+
+  private Map<String, MColumn> getColumns() {
     return columns;
   }
 
@@ -357,26 +404,14 @@ public class MTable {
     return compoundKeys;
   }
 
-  public String getSequenceName() {
-    return sequenceName;
-  }
-
   public void setSequenceName(String sequenceName) {
     this.sequenceName = sequenceName;
   }
 
-  public int getSequenceInitial() {
-    return sequenceInitial;
-  }
-
   public void setSequenceInitial(int sequenceInitial) {
     this.sequenceInitial = sequenceInitial;
   }
 
-  public int getSequenceAllocate() {
-    return sequenceAllocate;
-  }
-
   public void setSequenceAllocate(int sequenceAllocate) {
     this.sequenceAllocate = sequenceAllocate;
   }
@@ -399,22 +434,12 @@ public class MTable {
     this.identityType = identityType;
   }
 
-  /**
-   * Returns the identity type to use for this table.
-   * <p>
-   * If set then this overrides the platform default so for UUID generated values
-   * or DB's supporting both sequences and autoincrement.
-   */
-  public IdentityType getIdentityType() {
-    return identityType;
-  }
-
   /**
    * Return the list of columns that make the primary key.
    */
   public List<MColumn> primaryKeyColumns() {
     List<MColumn> pk = new ArrayList<MColumn>(3);
-    for (MColumn column : columns.values()) {
+    for (MColumn column : allColumns()) {
       if (column.isPrimaryKey()) {
         pk.add(column);
       }
@@ -473,7 +498,7 @@ public class MTable {
    */
   public MColumn addColumn(String dbCol, String columnDefn, boolean notnull) {
 
-    MColumn existingColumn = columns.get(dbCol);
+    MColumn existingColumn = getColumn(dbCol);
     if (existingColumn != null) {
       if (notnull) {
         existingColumn.setNotnull(true);
@@ -507,12 +532,12 @@ public class MTable {
   /**
    * Add a 'drop column' to the diff.
    */
-  private void diffDropColumn(ModelDiff modelDiff, MColumn existingColumn) {
+  private void diffDropColumn(ModelDiff modelDiff, MColumn existingColumn, int columnPosition, MTable newTable) {
 
     DropColumn dropColumn = new DropColumn();
     dropColumn.setTableName(name);
     dropColumn.setColumnName(existingColumn.getName());
-    if (withHistory) {
+    if (withHistory && !existingColumn.isHistoryExclude()) {
       // These dropColumns should occur on the history
       // table as well as the base table
       dropColumn.setWithHistory(Boolean.TRUE);
@@ -521,6 +546,16 @@ public class MTable {
     modelDiff.addDropColumn(dropColumn);
   }
 
+  /**
+   * Register a pending un-applied drop column.
+   * <p>
+   * This means this column still needs to be included in history views/triggers etc even
+   * though it is not part of the current model.
+   */
+  public void registerPendingDropColumn(String columnName) {
+    droppedColumns.add(columnName);
+  }
+
   private int toInt(BigInteger value) {
     return (value == null) ? 0 : value.intValue();
   }
@@ -532,7 +567,7 @@ public class MTable {
   /**
    * Check if there are duplicate foreign keys.
    * <p>
-   *   This can occur when an ManyToMany relates back to itself.
+   * This can occur when an ManyToMany relates back to itself.
    * </p>
    */
   public void checkDuplicateForeignKeys() {
@@ -563,7 +598,7 @@ public class MTable {
    */
   public void adjustReferences(ModelContainer modelContainer) {
 
-    Collection<MColumn> cols = columns.values();
+    Collection<MColumn> cols = allColumns();
     for (MColumn col : cols) {
       String references = col.getReferences();
       if (references != null) {
@@ -583,7 +618,7 @@ public class MTable {
    */
   private String extractBaseTable(String references) {
     int lastDot = references.lastIndexOf('.');
-    return references.substring(0,lastDot);
+    return references.substring(0, lastDot);
   }
 
   /**
@@ -592,7 +627,7 @@ public class MTable {
    */
   private String deriveReferences(String references, String draftTableName) {
     int lastDot = references.lastIndexOf('.');
-    return draftTableName+"."+references.substring(lastDot+1);
+    return draftTableName + "." + references.substring(lastDot + 1);
   }
 
 }

src/main/java/com/avaje/ebean/dbmigration/model/MigrationModel.java

@@ -52,7 +52,7 @@ public class MigrationModel {
     List<MigrationResource> resources = new ArrayList<MigrationResource>();
 
     for (File xmlFile: xmlFiles) {
-      resources.add(new MigrationResource(xmlFile));
+      resources.add(new MigrationResource(xmlFile, createVersion(xmlFile)));
     }
 
     // sort into version order before applying
@@ -60,7 +60,7 @@ public class MigrationModel {
 
     for (MigrationResource migrationResource: resources) {
       logger.debug("read {}", migrationResource);
-      model.apply(migrationResource.read());
+      model.apply(migrationResource.read(), migrationResource.getVersion());
     }
 
     // remember the last version
@@ -69,6 +69,12 @@ public class MigrationModel {
     }
   }
 
+  private MigrationVersion createVersion(File xmlFile) {
+    String fileName = xmlFile.getName();
+    String versionName = fileName.substring(0, fileName.length() - modelSuffix.length());
+    return MigrationVersion.parse(versionName);
+  }
+
   public String getNextVersion(String initialVersion) {
 
     return lastVersion == null ? initialVersion : lastVersion.nextVersion();

src/main/java/com/avaje/ebean/dbmigration/model/MigrationResource.java

@@ -17,9 +17,9 @@ public class MigrationResource implements Comparable<MigrationResource> {
   /**
    * Construct with a migration xml file.
    */
-  public MigrationResource(File migrationFile) {
+  public MigrationResource(File migrationFile, MigrationVersion version) {
     this.migrationFile = migrationFile;
-    this.version = MigrationVersion.parse(migrationFile.getName());
+    this.version = version;
   }
 
   public String toString() {

src/main/java/com/avaje/ebean/dbmigration/model/MigrationVersion.java

@@ -1,5 +1,7 @@
 package com.avaje.ebean.dbmigration.model;
 
+import java.util.Arrays;
+
 /**
  * The version of a migration used so that migrations are processed in order.
  */
@@ -15,23 +17,74 @@ public class MigrationVersion implements Comparable<MigrationVersion> {
    */
   private final int[] ordering;
 
-  private MigrationVersion(String raw, int[] ordering) {
+  private final boolean[] underscores;
+
+  private final String comment;
+
+  private MigrationVersion(String raw, int[] ordering, boolean[] underscores, String comment) {
     this.raw = raw;
     this.ordering = ordering;
+    this.underscores = underscores;
+    this.comment = comment;
   }
 
   public String toString() {
     return raw;
   }
 
+  /**
+   * Return the version comment.
+   */
+  public String getComment() {
+    return comment;
+  }
 
+  /**
+   * Return the version in raw form.
+   */
+  public String getRaw() {
+    return raw;
+  }
+
+  /**
+   * Return the trimmed version excluding version comment and un-parsable string.
+   */
+  public String asString() {
+    return formattedVersion(false, false);
+  }
+
+  /**
+   * Return the trimmed version with any underscores replaced with '.'
+   */
+  public String normalised() {
+    return formattedVersion(true, false);
+  }
+
+  /**
+   * Return the next version based on this version.
+   */
   public String nextVersion() {
+    return formattedVersion(false, true);
+  }
+
+  /**
+   * Returns the version part of the string.
+   *
+   * Normalised means always use '.' delimiters (no underscores).
+   * NextVersion means bump/increase the last version number by 1.
+   */
+  private String formattedVersion(boolean normalised, boolean nextVersion) {
     StringBuilder sb = new StringBuilder();
     for (int i = 0; i < ordering.length; i++) {
-      if (i < ordering.length -1 ) {
-        sb.append(ordering[i]).append(".");
+      if (i < ordering.length - 1) {
+        sb.append(ordering[i]);
+        if (normalised) {
+          sb.append('.');
+        } else {
+          sb.append(underscores[i] ? '_' : '.');
+        }
       } else {
-        sb.append(ordering[i]+1);
+        sb.append((nextVersion) ? ordering[i] + 1 : ordering[i]);
       }
     }
     return sb.toString();
@@ -54,33 +107,54 @@ public class MigrationVersion implements Comparable<MigrationVersion> {
     return 0;
   }
 
+  /**
+   * Parse the raw version string and just return the leading version number;
+   */
+  public static String trim(String raw) {
+    return parse(raw).asString();
+  }
+
   /**
    * Parse the raw version string into a MigrationVersion.
    */
   public static MigrationVersion parse(String raw) {
 
-    String value = raw.replace("__",".");
-    value = value.replace('_','.');
+    String comment = "";
+    String value = raw;
+    int commentStart = raw.indexOf("__");
+    if (commentStart > -1) {
+      // trim off the trailing comment
+      comment = raw.substring(commentStart + 2);
+      value = value.substring(0, commentStart);
+    }
+
+    value = value.replace('_', '.');
 
     String[] sections = value.split("\\.");
 
+    boolean[] underscores = new boolean[sections.length];
     int[] ordering = new int[sections.length];
 
+    int delimiterPos = 0;
     int stopIndex = 0;
     for (int i = 0; i < sections.length; i++) {
       try {
         ordering[i] = Integer.parseInt(sections[i]);
         stopIndex++;
+
+        delimiterPos += sections[i].length();
+        underscores[i] = (delimiterPos < raw.length() - 1 && raw.charAt(delimiterPos) == '_');
+        delimiterPos++;
       } catch (NumberFormatException e) {
         // stop parsing
         break;
       }
     }
 
-    int[] actualOrder = new int[stopIndex];
-    System.arraycopy(ordering, 0, actualOrder, 0, stopIndex);
+    int[] actualOrder = Arrays.copyOf(ordering, stopIndex);
+    boolean[] actualUnderscores = Arrays.copyOf(underscores, stopIndex);
 
-    return new MigrationVersion(raw, actualOrder);
+    return new MigrationVersion(raw, actualOrder, actualUnderscores, comment);
   }
 
 }

src/main/java/com/avaje/ebean/dbmigration/model/ModelContainer.java

@@ -4,6 +4,7 @@ import com.avaje.ebean.dbmigration.migration.AddColumn;
 import com.avaje.ebean.dbmigration.migration.AddHistoryTable;
 import com.avaje.ebean.dbmigration.migration.AlterColumn;
 import com.avaje.ebean.dbmigration.migration.ChangeSet;
+import com.avaje.ebean.dbmigration.migration.ChangeSetType;
 import com.avaje.ebean.dbmigration.migration.CreateIndex;
 import com.avaje.ebean.dbmigration.migration.CreateTable;
 import com.avaje.ebean.dbmigration.migration.DropColumn;
@@ -12,7 +13,6 @@ import com.avaje.ebean.dbmigration.migration.DropIndex;
 import com.avaje.ebean.dbmigration.migration.DropTable;
 import com.avaje.ebean.dbmigration.migration.Migration;
 
-import java.util.Collection;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -28,23 +28,23 @@ public class ModelContainer {
   /**
    * All the tables in the model.
    */
-  private Map<String, MTable> tables = new LinkedHashMap<String, MTable>();
+  private final Map<String, MTable> tables = new LinkedHashMap<String, MTable>();
 
   /**
    * All the non unique non foreign key indexes.
    */
-  private Map<String, MIndex> indexes = new LinkedHashMap<String, MIndex>();
+  private final Map<String, MIndex> indexes = new LinkedHashMap<String, MIndex>();
+
+  private final PendingDrops pendingDrops = new PendingDrops();
 
   public ModelContainer() {
-
   }
 
   /**
    * Adjust the FK references on all the draft tables.
    */
   public void adjustDraftReferences() {
-    Collection<MTable> tables = this.tables.values();
-    for (MTable table : tables) {
+    for (MTable table : this.tables.values()) {
       if (table.isDraft()) {
         table.adjustReferences(this);
       }
@@ -82,14 +82,31 @@ public class ModelContainer {
   /**
    * Apply a migration with associated changeSets to the model.
    */
-  public void apply(Migration migration) {
+  public void apply(Migration migration, MigrationVersion version) {
 
     List<ChangeSet> changeSets = migration.getChangeSet();
     for (ChangeSet changeSet : changeSets) {
-      applyChangeSet(changeSet);
+      boolean pending = changeSet.getType() == ChangeSetType.PENDING_DROPS;
+      if (pending) {
+        // un-applied drop columns etc
+        pendingDrops.add(version, changeSet);
+
+      } else if (isDropsFor(changeSet)) {
+        pendingDrops.appliedDropsFor(changeSet);
+      }
+      if (!isDropsFor(changeSet)) {
+        applyChangeSet(changeSet);
+      }
     }
   }
 
+  /**
+   * Return true if the changeSet contains drops for a previous PENDING_DROPS changeSet.
+   */
+  private boolean isDropsFor(ChangeSet changeSet) {
+    return changeSet.getDropsFor() != null;
+  }
+
   /**
    * Apply a changeSet to the model.
    */
@@ -245,4 +262,53 @@ public class ModelContainer {
 
     indexes.put(indexName, new MIndex(indexName, tableName, columnNames));
   }
+
+  /**
+   * Return the list of versions containing un-applied pending drops.
+   */
+  public List<String> getPendingDrops() {
+    return pendingDrops.pendingDrops();
+  }
+
+  /**
+   * Return the migration for the pending drops for a given version.
+   */
+  public Migration migrationForPendingDrop(String pendingVersion) {
+    return pendingDrops.migrationForVersion(pendingVersion);
+  }
+
+  /**
+   * Register the drop columns on history tables that have not been applied yet.
+   */
+  public void registerPendingHistoryDropColumns(ModelContainer newModel) {
+    pendingDrops.registerPendingHistoryDropColumns(newModel);
+  }
+
+  /**
+   * Register any pending drop columns on history tables.  These columns are now not in the current
+   * logical model but we still need to include them in the history views and triggers until they
+   * are actually dropped.
+   */
+  public void registerPendingHistoryDropColumns(ChangeSet changeSet) {
+    for (Object change : changeSet.getChangeSetChildren()) {
+      if (change instanceof DropColumn) {
+        DropColumn dropColumn = (DropColumn) change;
+        if (Boolean.TRUE.equals(dropColumn.isWithHistory())) {
+          registerPendingDropColumn(dropColumn);
+        }
+      }
+    }
+  }
+
+  /**
+   * Register a drop column on a history tables that has not been applied yet.
+   */
+  private void registerPendingDropColumn(DropColumn dropColumn) {
+
+    MTable table = getTable(dropColumn.getTableName());
+    if (table == null) {
+      throw new IllegalArgumentException("Table ["+dropColumn.getTableName()+"] not found?");
+    }
+    table.registerPendingDropColumn(dropColumn.getColumnName());
+  }
 }

src/main/java/com/avaje/ebean/dbmigration/model/ModelDiff.java

@@ -66,16 +66,14 @@ public class ModelDiff {
   public Migration getMigration() {
 
     Migration migration = new Migration();
-    ChangeSet applyChangeSet = getApplyChangeSet();
-    if (!applyChangeSet.getChangeSetChildren().isEmpty()) {
+    if (!applyChanges.isEmpty()) {
       // add a non empty apply changeSet
-      migration.getChangeSet().add(applyChangeSet);
+      migration.getChangeSet().add(getApplyChangeSet());
     }
 
-    ChangeSet dropChangeSet = getDropChangeSet();
-    if (!dropChangeSet.getChangeSetChildren().isEmpty()) {
+    if (!dropChanges.isEmpty()) {
       // add a non empty drop changeSet
-      migration.getChangeSet().add(dropChangeSet);
+      migration.getChangeSet().add(getDropChangeSet());
     }
     return migration;
   }
@@ -83,14 +81,14 @@ public class ModelDiff {
   /**
    * Return the list of 'apply' changes.
    */
-  public List<Object> getApplyChanges() {
+  List<Object> getApplyChanges() {
     return applyChanges;
   }
 
   /**
    * Return the list of 'drop' changes.
    */
-  public List<Object> getDropChanges() {
+  List<Object> getDropChanges() {
     return dropChanges;
   }
 
@@ -108,10 +106,10 @@ public class ModelDiff {
   /**
    * Return the 'drop' changeSet.
    */
-  public ChangeSet getDropChangeSet() {
+  ChangeSet getDropChangeSet() {
     // put the changes into a ChangeSet
     ChangeSet createChangeSet = new ChangeSet();
-    createChangeSet.setType(ChangeSetType.DROP);
+    createChangeSet.setType(ChangeSetType.PENDING_DROPS);
     createChangeSet.getChangeSetChildren().addAll(dropChanges);
     return createChangeSet;
   }
@@ -156,6 +154,12 @@ public class ModelDiff {
       }
     }
 
+    // register un-applied ones from the previous migrations
+    baseModel.registerPendingHistoryDropColumns(newModel);
+    if (!dropChanges.isEmpty()) {
+      // register new ones created just now as part of this diff
+      newModel.registerPendingHistoryDropColumns(getDropChangeSet());
+    }
   }
 
   protected void addDropTable(MTable existingTable) {

src/main/java/com/avaje/ebean/dbmigration/model/PendingDrops.java

@@ -0,0 +1,263 @@
+package com.avaje.ebean.dbmigration.model;
+
+import com.avaje.ebean.dbmigration.migration.ChangeSet;
+import com.avaje.ebean.dbmigration.migration.ChangeSetType;
+import com.avaje.ebean.dbmigration.migration.DropColumn;
+import com.avaje.ebean.dbmigration.migration.DropTable;
+import com.avaje.ebean.dbmigration.migration.Migration;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.List;
+
+/**
+ * The migrations with pending un-applied drops.
+ */
+public class PendingDrops {
+
+  private final LinkedHashMap<String, Entry> map = new LinkedHashMap<String, Entry>();
+
+  /**
+   * Add a 'pending drops' changeSet for the given version.
+   */
+  public void add(MigrationVersion version, ChangeSet changeSet) {
+
+    Entry entry = map.get(version.normalised());
+    if (entry == null) {
+      entry = new Entry(version);
+      map.put(version.normalised(), entry);
+    }
+    entry.add(changeSet);
+  }
+
+  /**
+   * Return the list of versions with pending drops.
+   */
+  public List<String> pendingDrops() {
+
+    List<String> versions = new ArrayList<String>();
+    for (Entry value : map.values()) {
+      if (value.hasPendingDrops()) {
+        versions.add(value.version.asString());
+      }
+    }
+    return versions;
+  }
+
+  /**
+   * All the pending drops for this migration version have been applied so we need
+   * to remove the (unsuppressed) pending drops for this version.
+   */
+  public boolean appliedDropsFor(ChangeSet changeSet) {
+
+    MigrationVersion version = MigrationVersion.parse(changeSet.getDropsFor());
+
+    Entry entry = map.get(version.normalised());
+    if (entry.removeDrops(changeSet)) {
+      // it had no suppressForever changeSets so remove completely
+      map.remove(version.normalised());
+      return true;
+    }
+
+    return false;
+  }
+
+  /**
+   * Return the migration for the pending drops from a version.
+   * <p>
+   * The value of version can be "next" to find the first un-applied pending drops.
+   * </p>
+   */
+  public Migration migrationForVersion(String pendingVersion) {
+
+    Entry entry = getEntry(pendingVersion);
+
+    Migration migration = new Migration();
+    Iterator<ChangeSet> it = entry.list.iterator();
+    while (it.hasNext()) {
+      ChangeSet changeSet = it.next();
+      if (!isSuppressForever(changeSet)) {
+        it.remove();
+        changeSet.setType(ChangeSetType.APPLY);
+        changeSet.setDropsFor(entry.version.asString());
+        migration.getChangeSet().add(changeSet);
+      }
+    }
+
+    if (migration.getChangeSet().isEmpty()) {
+      throw new IllegalArgumentException("The remaining pendingDrops changeSets in migration ["+pendingVersion+"] are suppressDropsForever=true and can't be applied");
+    }
+
+    if (!entry.containsSuppressForever()) {
+      // we can remove it completely as it has no suppressForever changes
+      map.remove(entry.version.normalised());
+    }
+
+    return migration;
+  }
+
+  private Entry getEntry(String pendingVersion) {
+
+    if ("next".equalsIgnoreCase(pendingVersion)) {
+      Iterator<Entry> it = map.values().iterator();
+      if (it.hasNext()) {
+        return it.next();
+      }
+    } else {
+      Entry remove = map.get(MigrationVersion.parse(pendingVersion).normalised());
+      if (remove != null) {
+        return remove;
+      }
+    }
+    throw new IllegalArgumentException("No 'pendingDrops' changeSets for migration version [" + pendingVersion + "] found");
+  }
+
+  /**
+   * Register pending drop columns on history tables to the new model.
+   */
+  public void registerPendingHistoryDropColumns(ModelContainer newModel) {
+
+    for (Entry entry : map.values()) {
+      for (ChangeSet changeSet : entry.list) {
+        newModel.registerPendingHistoryDropColumns(changeSet);
+      }
+    }
+  }
+
+  /**
+   * Return true if there is an Entry for the given version.
+   */
+  boolean testContainsEntryFor(MigrationVersion version) {
+    return map.containsKey(version.normalised());
+  }
+
+  /**
+   * Return the Entry for the given version.
+   */
+  Entry testGetEntryFor(MigrationVersion version) {
+    return map.get(version.normalised());
+  }
+
+  static class Entry {
+
+    final MigrationVersion version;
+
+    final List<ChangeSet> list = new ArrayList<ChangeSet>();
+
+    Entry(MigrationVersion version) {
+      this.version = version;
+    }
+
+    void add(ChangeSet changeSet) {
+      list.add(changeSet);
+    }
+
+    /**
+     * Return true if this contains suppressForever changeSets.
+     */
+    boolean containsSuppressForever() {
+      for (ChangeSet changeSet : list) {
+        if (isSuppressForever(changeSet)) {
+          return true;
+        }
+      }
+      return false;
+    }
+
+    /**
+     * Return true if this contains drops that can be applied / migrated.
+     */
+    boolean hasPendingDrops() {
+      for (ChangeSet changeSet : list) {
+        if (!isSuppressForever(changeSet)) {
+          return true;
+        }
+      }
+      return false;
+    }
+
+    /**
+     * Remove the drops that are not suppressForever and return true if that
+     * removed all the changeSets (and there are no suppressForever ones).
+     */
+    boolean removeDrops(ChangeSet appliedDrops) {
+
+      Iterator<ChangeSet> iterator = list.iterator();
+      while (iterator.hasNext()) {
+        ChangeSet next = iterator.next();
+        if (!isSuppressForever(next)) {
+          removeMatchingChanges(next, appliedDrops);
+          if (next.getChangeSetChildren().isEmpty()) {
+            iterator.remove();
+          }
+        }
+      }
+
+      return list.isEmpty();
+    }
+
+    /**
+     * Remove the applied drops from the pending ones matching by table name and column name.
+     */
+    private void removeMatchingChanges(ChangeSet pendingDrops, ChangeSet appliedDrops) {
+
+      List<Object> pending = pendingDrops.getChangeSetChildren();
+      Iterator<Object> iterator = pending.iterator();
+      while (iterator.hasNext()) {
+        Object pendingDrop = iterator.next();
+        if (pendingDrop instanceof DropColumn && dropColumnIn((DropColumn)pendingDrop, appliedDrops)) {
+          iterator.remove();
+
+        } else if (pendingDrop instanceof DropTable && dropTableIn((DropTable)pendingDrop, appliedDrops)) {
+          iterator.remove();
+        }
+      }
+    }
+
+    /**
+     * Return true if the pendingDrop is contained in the appliedDrops.
+     */
+    private boolean dropTableIn(DropTable pendingDrop, ChangeSet appliedDrops) {
+      for (Object o : appliedDrops.getChangeSetChildren()) {
+        if (o instanceof DropTable && sameTable(pendingDrop, (DropTable)o)) {
+          return true;
+        }
+      }
+      return false;
+    }
+
+    /**
+     * Return true if the pendingDrop is contained in the appliedDrops.
+     */
+    private boolean dropColumnIn(DropColumn pendingDrop, ChangeSet appliedDrops) {
+      for (Object o : appliedDrops.getChangeSetChildren()) {
+        if (o instanceof DropColumn && sameColumn(pendingDrop, (DropColumn) o)) {
+          return true;
+        }
+      }
+      return false;
+    }
+
+    /**
+     * Return true if the DropTable match by table name.
+     */
+    private boolean sameTable(DropTable pendingDrop, DropTable o) {
+      return pendingDrop.getName().equals(o.getName());
+    }
+
+    /**
+     * Return true if the DropColumns match by table and column name.
+     */
+    private boolean sameColumn(DropColumn pending, DropColumn o) {
+      return pending.getColumnName().equals(o.getColumnName())
+          && pending.getTableName().equals(o.getTableName());
+    }
+
+  }
+
+  private static boolean isSuppressForever(ChangeSet next) {
+    return Boolean.TRUE.equals(next.isSuppressDropsForever());
+  }
+
+}

src/main/java/com/avaje/ebean/dbmigration/model/PlatformDdlWriter.java

@@ -3,9 +3,11 @@ package com.avaje.ebean.dbmigration.model;
 import com.avaje.ebean.config.DbMigrationConfig;
 import com.avaje.ebean.config.ServerConfig;
 import com.avaje.ebean.config.dbplatform.DatabasePlatform;
+import com.avaje.ebean.dbmigration.ddlgeneration.DdlBuffer;
 import com.avaje.ebean.dbmigration.ddlgeneration.DdlHandler;
 import com.avaje.ebean.dbmigration.ddlgeneration.DdlWrite;
 import com.avaje.ebean.dbmigration.migration.ChangeSet;
+import com.avaje.ebean.dbmigration.migration.ChangeSetType;
 import com.avaje.ebean.dbmigration.migration.Migration;
 
 import java.io.File;
@@ -43,7 +45,7 @@ public class PlatformDdlWriter {
 
     List<ChangeSet> changeSets = dbMigration.getChangeSet();
     for (ChangeSet changeSet : changeSets) {
-      if (!changeSet.getChangeSetChildren().isEmpty()) {
+      if (isApply(changeSet)) {
         handler.generate(write, changeSet);
       }
     }
@@ -52,6 +54,13 @@ public class PlatformDdlWriter {
     writePlatformDdl(write, writePath, fullVersion);
   }
 
+  /**
+   * Return true if the changeSet is APPLY and not empty.
+   */
+  private boolean isApply(ChangeSet changeSet) {
+    return changeSet.getType() == ChangeSetType.APPLY && !changeSet.getChangeSetChildren().isEmpty();
+  }
+
   /**
    * Write the ddl files.
    */
@@ -65,26 +74,6 @@ public class PlatformDdlWriter {
       } finally {
         applyWriter.close();
       }
-
-      if (!config.isSuppressRollback() && !write.isApplyRollbackEmpty()) {
-        FileWriter applyRollbackWriter = createWriter(resourcePath, fullVersion, config.getRollbackPath(), config.getRollbackSuffix());
-        try {
-          writeApplyRollbackDdl(applyRollbackWriter, write);
-          applyRollbackWriter.flush();
-        } finally {
-          applyRollbackWriter.close();
-        }
-      }
-    }
-
-    if (!write.isDropEmpty()) {
-      FileWriter dropWriter = createWriter(resourcePath, fullVersion, config.getDropPath(), config.getDropSuffix());
-      try {
-        writeDropDdl(dropWriter, write);
-        dropWriter.flush();
-      } finally {
-        dropWriter.close();
-      }
     }
   }
 
@@ -116,29 +105,19 @@ public class PlatformDdlWriter {
   protected void writeApplyDdl(Writer writer, DdlWrite write) throws IOException {
 
     // merge the apply buffers in the appropriate order
+    prependDropDependencies(writer, write.applyDropDependencies());
+    writer.append("-- apply changes\n");
     writer.append(write.apply().getBuffer());
     writer.append(write.applyForeignKeys().getBuffer());
     writer.append(write.applyHistory().getBuffer());
   }
 
-  /**
-   * Write the 'Rollback' DDL buffers to the writer.
-   */
-  protected void writeApplyRollbackDdl(Writer writer, DdlWrite write) throws IOException {
-
-    // merge the rollback buffers in the appropriate order
-    writer.append(write.rollbackForeignKeys().getBuffer());
-    writer.append(write.rollback().getBuffer());
-  }
-
-  /**
-   * Write the 'Drop' DDL buffers to the writer.
-   */
-  protected void writeDropDdl(Writer writer, DdlWrite write) throws IOException {
-
-    // merge the rollback buffers in the appropriate order
-    writer.append(write.dropHistory().getBuffer());
-    writer.append(write.drop().getBuffer());
+  private void prependDropDependencies(Writer writer, DdlBuffer buffer) throws IOException {
+    if (!buffer.isEmpty()) {
+      writer.append("-- drop dependencies\n");
+      writer.append(buffer.getBuffer());
+      writer.append("\n");
+    }
   }
 
   /**

src/main/java/com/avaje/ebean/dbmigration/model/build/ModelBuildContext.java

@@ -158,7 +158,7 @@ public class ModelBuildContext {
     int fkCount = 0;
     int ixCount = 0;
     int uqCount = 0;
-    Collection<MColumn> cols = draftTable.getColumns().values();
+    Collection<MColumn> cols = draftTable.allColumns();
     for (MColumn col: cols) {
       if (col.getForeignKeyName() != null) {
         // Note that we adjust the 'references' table later in a second pass

src/main/java/com/avaje/ebean/dbmigration/model/build/ModelBuildPropertyVisitor.java

@@ -84,7 +84,7 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
     table.setPkName(determinePrimaryKeyName());
 
     // check if indexes on foreign keys should be suppressed
-    for (MColumn column : table.getColumns().values()) {
+    for (MColumn column : table.allColumns()) {
       if (hasValue(column.getForeignKeyIndex())) {
         if (indexSet.contains(column.getName())) {
           // suppress index on foreign key as there is already

src/main/java/com/avaje/ebean/text/PathProperties.java

@@ -92,7 +92,7 @@ public class PathProperties {
   /**
    * Get the properties for a given path.
    */
-  public Set<String> get(String path) {
+  public LinkedHashSet<String> get(String path) {
     Props props = pathMap.get(path);
     return props == null ? null : props.getProperties();
   }
@@ -109,7 +109,7 @@ public class PathProperties {
   /**
    * Set the properties for a given path.
    */
-  public void put(String path, Set<String> properties) {
+  public void put(String path, LinkedHashSet<String> properties) {
     pathMap.put(path, new Props(this, null, path, properties));
   }
 
@@ -160,9 +160,9 @@ public class PathProperties {
     private final String parentPath;
     private final String path;
 
-    private final Set<String> propSet;
+    private final LinkedHashSet<String> propSet;
 
-    private Props(PathProperties owner, String parentPath, String path, Set<String> propSet) {
+    private Props(PathProperties owner, String parentPath, String path, LinkedHashSet<String> propSet) {
       this.owner = owner;
       this.path = path;
       this.parentPath = parentPath;
@@ -195,7 +195,7 @@ public class PathProperties {
     /**
      * Return the properties for this property set.
      */
-    public Set<String> getProperties() {
+    public LinkedHashSet<String> getProperties() {
       return propSet;
     }
 

src/main/java/com/avaje/ebeaninternal/api/CQueryPlanKey.java

@@ -0,0 +1,14 @@
+package com.avaje.ebeaninternal.api;
+
+/**
+ * Key used for caching query plans for ORM and RawSql queries.
+ */
+public interface CQueryPlanKey {
+
+  /**
+   * Used by read audit such that we can log read audit entries without the full sql
+   * (which would make the read audit logs verbose).
+   */
+  String getPartialKey();
+
+}

src/main/java/com/avaje/ebeaninternal/api/HashQuery.java

@@ -5,32 +5,18 @@ package com.avaje.ebeaninternal.api;
  */
 public class HashQuery {
 
-  private final HashQueryPlan planHash;
+  private final CQueryPlanKey planHash;
   
   private final int bindHash;
 
   /**
    * Create the HashQuery.
    */
-  public HashQuery(HashQueryPlan planHash, int bindHash) {
+  public HashQuery(CQueryPlanKey planHash, int bindHash) {
     this.planHash = planHash;
     this.bindHash = bindHash;
   }
 
-  /**
-   * Return the query plan hash.
-   */
-  public HashQueryPlan getPlanHash() {
-    return planHash;
-  }
-
-  /**
-   * Return the bind values hash.
-   */
-  public int getBindHash() {
-    return bindHash;
-  }
-
   public int hashCode() {
     int hc = 31 * planHash.hashCode();
     hc = 31 * hc + bindHash;

src/main/java/com/avaje/ebeaninternal/api/HashQueryPlanBuilder.java

@@ -1,5 +1,7 @@
 package com.avaje.ebeaninternal.api;
 
+import java.util.Set;
+
 /**
  * Used to build HashQueryPlan instances.
  */
@@ -9,21 +11,19 @@ public class HashQueryPlanBuilder {
   
   private int bindCount;
 
-  private String rawSql;
-  
   public HashQueryPlanBuilder() {
-    this.planHash = 31;
+    this.planHash = 92821;
   }
 
   public String toString() {
-    return planHash+":"+bindCount+(rawSql != null ? ":r" : "");
+    return planHash+":"+bindCount;
   }
   
   /**
    * Add a class to the hash calculation.
    */
   public HashQueryPlanBuilder add(Class<?> cls) {
-    planHash = planHash * 31 + cls.getName().hashCode();
+    planHash = planHash * 92821 + cls.getName().hashCode();
     return this;
   }
 
@@ -31,7 +31,22 @@ public class HashQueryPlanBuilder {
    * Add an object to the hash calculation.
    */
   public HashQueryPlanBuilder add(Object object) {
-    planHash = planHash * 31 + (object == null ? 0 : object.hashCode());
+    planHash = planHash * 92821 + (object == null ? 0 : object.hashCode());
+    return this;
+  }
+
+  /**
+   * Add the set with order being important.
+   */
+  public HashQueryPlanBuilder addOrdered(Set<?> set) {
+    if (set == null) {
+      add(false);
+    } else {
+      add(true);
+      for (Object o : set) {
+        add(o);
+      }
+    }
     return this;
   }
 
@@ -39,7 +54,7 @@ public class HashQueryPlanBuilder {
    * Add an integer to the hash calculation.
    */
   public HashQueryPlanBuilder add(int hashValue) {
-    planHash = planHash * 31 + (hashValue);
+    planHash = planHash * 92821 + (hashValue);
     return this;
   }
   
@@ -47,7 +62,7 @@ public class HashQueryPlanBuilder {
    * Add a boolean to the hash calculation.
    */
   public HashQueryPlanBuilder add(boolean booleanValue) {
-    planHash = planHash * 31 + (booleanValue ? 31 : 0);
+    planHash = planHash * 92821 + (booleanValue ? 92821 : 0);
     return this;
   }
   
@@ -58,19 +73,24 @@ public class HashQueryPlanBuilder {
     bindCount += extraBindCount;
   }
 
-  /**
-   * Add raw sql to the hash.
-   */
-  public void addRawSql(String rawSql) {
-    this.rawSql = rawSql;
+  public void bindIfNotNull(Object someValue) {
+    if (someValue != null) {
+      bindCount++;
+    }
   }
 
   /**
    * Build and return the calculated HashQueryPlan.
    */
-  public HashQueryPlan build() {
-    return new HashQueryPlan(rawSql, planHash, bindCount);
+  public String build() {
+    return planHash+"_"+bindCount;
   }
 
-  
+  public int getPlanHash() {
+    return planHash;
+  }
+
+  public int getBindCount() {
+    return bindCount;
+  }
 }

src/main/java/com/avaje/ebeaninternal/api/LoadContext.java

@@ -5,6 +5,9 @@ import com.avaje.ebean.bean.EntityBeanIntercept;
 import com.avaje.ebean.bean.ObjectGraphNode;
 import com.avaje.ebean.bean.PersistenceContext;
 import com.avaje.ebeaninternal.server.core.OrmQueryRequest;
+import com.avaje.ebeaninternal.server.querydefn.OrmQueryProperties;
+
+import java.util.List;
 
 /**
  * Controls the loading of reference objects for a query instance.
@@ -22,17 +25,7 @@ public interface LoadContext {
 	 */
 	void executeSecondaryQueries(OrmQueryRequest<?> parentRequest);
 
-	/**
-	 * Register any secondary queries (+query or +lazy) with their
-	 * appropriate LoadBeanContext or LoadManyContext.
-	 * <p>
-	 * This is so the LoadBeanContext or LoadManyContext use the 
-	 * defined query for +query and +lazy execution.
-	 * </p>
-	 */
-	void registerSecondaryQueries(SpiQuery<?> query);
-	
-	/**
+  /**
 	 * Return the node for a given path which is used by AutoTune profiling.
 	 */
 	ObjectGraphNode getObjectGraphNode(String path);

src/main/java/com/avaje/ebeaninternal/api/SpiEbeanServer.java

@@ -13,11 +13,8 @@ import com.avaje.ebean.config.ServerConfig;
 import com.avaje.ebean.config.dbplatform.DatabasePlatform;
 import com.avaje.ebean.event.readaudit.ReadAuditLogger;
 import com.avaje.ebean.event.readaudit.ReadAuditPrepare;
-import com.avaje.ebeaninternal.server.core.SpiOrmQueryRequest;
-import com.avaje.ebean.dbmigration.DdlGenerator;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
 import com.avaje.ebeaninternal.server.query.CQuery;
-import com.avaje.ebeaninternal.server.query.CQueryEngine;
 import com.avaje.ebeaninternal.server.transaction.RemoteTransactionEvent;
 
 import java.util.List;
@@ -130,22 +127,11 @@ public interface SpiEbeanServer extends EbeanServer, BeanLoader, BeanCollectionL
    */
   void remoteTransactionEvent(RemoteTransactionEvent event);
 
-  /**
-   * Create a query request object.
-   */
-  <T> SpiOrmQueryRequest<T> createQueryRequest(BeanDescriptor<T> desc, SpiQuery<T> q,
-      Transaction t);
-
   /**
    * Compile a query.
    */
   <T> CQuery<T> compileQuery(Query<T> query, Transaction t);
 
-  /**
-   * Return the queryEngine for this server.
-   */
-  CQueryEngine getQueryEngine();
-
   /**
    * Execute the findId's query but without copying the query.
    * <p>

src/main/java/com/avaje/ebeaninternal/api/SpiExpression.java

@@ -17,32 +17,36 @@ public interface SpiExpression extends Expression {
    * </p>
    */
 	void containsMany(BeanDescriptor<?> desc, ManyWhereJoins whereManyJoins);
-	
-	/**
+
+  /**
+   * Prepare the expression. For example, compile sub-query expressions etc.
+   */
+  void prepareExpression(BeanQueryRequest<?> request);
+
+  /**
 	 * Calculate a hash value used to identify a query for AutoTune tuning.
 	 * <p>
 	 * That is, if the hash changes then the query will be considered different
 	 * from an AutoTune perspective and get different tuning.
 	 * </p>
 	 */
-	void queryAutoTuneHash(HashQueryPlanBuilder builder);
-	
-	/**
-	 * Calculate a hash value for the expression.
-	 * This includes the expression type and property but should exclude
-	 * the bind values.
-	 * <p>
-	 * This is used where queries are the same except for the bind values, in which
-	 * case the query execution plan can be reused.
-	 * </p>
-	 */
-	void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder);
-	
+	void queryPlanHash(HashQueryPlanBuilder builder);
+
 	/**
 	 * Return the hash value for the values that will be bound.
 	 */
 	int queryBindHash();
-	
+
+  /**
+   * Return true if the expression is the same without taking into account bind values.
+   */
+  boolean isSameByPlan(SpiExpression other);
+
+  /**
+   * Return true if the expression is the same with respect to bind values.
+   */
+  boolean isSameByBind(SpiExpression other);
+
 	/**
 	 * Add some sql to the query.
 	 * <p>
@@ -61,7 +65,7 @@ public interface SpiExpression extends Expression {
 	/**
 	 * Add the parameter values to be set against query. For each ? place holder
 	 * there should be a corresponding value that is added to the bindList.
-	 * 
+	 *
 	 * @param request
 	 *            the associated request.
 	 */
@@ -71,4 +75,10 @@ public interface SpiExpression extends Expression {
    * Validate all the properties/paths associated with this expression.
    */
   void validate(SpiExpressionValidation validation);
+
+  /**
+   * Return a copy of the expression for use in the query plan key.
+   */
+  SpiExpression copyForPlanKey();
+
 }

src/main/java/com/avaje/ebeaninternal/api/SpiExpressionList.java

@@ -1,17 +1,13 @@
 package com.avaje.ebeaninternal.api;
 
-import java.util.ArrayList;
-import java.util.List;
-
-import com.avaje.ebean.ExpressionFactory;
 import com.avaje.ebean.ExpressionList;
-import com.avaje.ebean.event.BeanQueryRequest;
-import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
+
+import java.util.List;
 
 /**
  * Internal extension of ExpressionList.
  */
-public interface SpiExpressionList<T> extends ExpressionList<T> {
+public interface SpiExpressionList<T> extends ExpressionList<T>, SpiExpression {
 
   /**
    * Return the underlying list of expressions.
@@ -23,52 +19,9 @@ public interface SpiExpressionList<T> extends ExpressionList<T> {
    */
   SpiExpressionList<?> trimPath(int prefixTrim);
     
-	/**
-	 * Restore the ExpressionFactory after deserialisation.
-	 */
-	void setExpressionFactory(ExpressionFactory expr);
-
-  /**
-   * Process "Many" properties populating ManyWhereJoins.
-   * <p>
-   * Predicates on Many properties require an extra independent join clause.
-   * </p>
-   */
-  void containsMany(BeanDescriptor<?> desc, ManyWhereJoins manyWhereJoins);
-	
 	/**
 	 * Return true if this list is empty.
 	 */
 	boolean isEmpty();
 
-	/**
-	 * Concatenate the expression sql into a String.
-	 * <p>
-	 * The list of expressions are evaluated in order building a sql statement
-	 * with bind parameters.
-	 * </p>
-	 */
-	String buildSql(SpiExpressionRequest request);
-
-	/**
-	 * Combine the expression bind values into a list.
-	 * <p>
-	 * Expressions are evaluated in order and all the resulting bind values are
-	 * returned as a List.
-	 * </p>
-	 * 
-	 * @return the list of all the bind values in order.
-	 */
-	ArrayList<Object> buildBindValues(SpiExpressionRequest request);
-	
-  /**
-   * Calculate a hash based on the expressions but excluding the actual bind
-   * values.
-   */
-  void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder);
-
-  /**
-   * Validate all the properties/paths used in this expression list.
-   */
-  void validate(SpiExpressionValidation validation);
 }

src/main/java/com/avaje/ebeaninternal/api/SpiExpressionRequest.java

@@ -1,11 +1,11 @@
 package com.avaje.ebeaninternal.api;
 
-import java.util.ArrayList;
-
 import com.avaje.ebeaninternal.server.core.JsonExpressionHandler;
 import com.avaje.ebeaninternal.server.core.SpiOrmQueryRequest;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
 
+import java.util.List;
+
 /**
  * Request object used for gathering expression sql and bind values.
  */
@@ -54,7 +54,7 @@ public interface SpiExpressionRequest {
 	/**
 	 * Return the ordered list of bind values for all expressions in this request.
 	 */
-	ArrayList<Object> getBindValues();
+	List<Object> getBindValues();
 
   /**
    * Increments the parameter index and returns that value.

src/main/java/com/avaje/ebeaninternal/api/SpiQuery.java

@@ -289,11 +289,6 @@ public interface SpiQuery<T> extends Query<T> {
    */
   void setBeanDescriptor(BeanDescriptor<?> desc);
 
-  /**
-   * Initialise/determine the joins required to support 'many' where clause predicates.
-   */
-  boolean initManyWhereJoins();
-
   /**
    * Return the joins required to support predicates on the many properties.
    */
@@ -319,31 +314,15 @@ public interface SpiQuery<T> extends Query<T> {
    */
   void setFilterMany(String prop, ExpressionList<?> filterMany);
 
-  /**
-   * Remove the query joins from query detail.
-   * <p>
-   * These are registered with the Load Context.
-   * </p>
-   */
-  List<OrmQueryProperties> removeQueryJoins();
-
-  /**
-   * Remove the lazy joins from query detail.
-   * <p>
-   * These are registered with the Load Context.
-   * </p>
-   */
-  List<OrmQueryProperties> removeLazyJoins();
-
   /**
    * Set the path of the many when +query/+lazy loading query is executed.
    */
   void setLazyLoadManyPath(String lazyLoadManyPath);
 
   /**
-   * Convert any many joins fetch joins to query joins.
+   * Convert joins as necessary to query joins etc.
    */
-  void convertManyFetchJoinsToQueryJoins(boolean allowOne, int queryBatch);
+  SpiQuerySecondary convertJoins();
 
   /**
    * Return the TransactionContext.
@@ -467,27 +446,13 @@ public interface SpiQuery<T> extends Query<T> {
   String getName();
 
   /**
-   * Calculate a hash used by AutoTune to identify when a query has changed
-   * (and hence potentially needs a new tuned query plan to be developed).
+   * Prepare the query which prepares sub-query expressions and calculates
+   * and returns the query plan key.
    * <p>
-   * Excludes bind values and occurs prior to AutoTune potentially
-   * tuning/modifying the query.
+   * The query plan excludes actual bind values (as they don't effect the query plan).
    * </p>
    */
-  HashQueryPlan queryAutoTuneHash(HashQueryPlanBuilder builder);
-
-  /**
-   * Identifies queries that are the same bar the bind variables.
-   * <p>
-   * This is used AFTER AutoTune has potentially tuned the query. This is
-   * used to identify and reused query plans (the final SQL string and
-   * associated SqlTree object).
-   * </p>
-   * <p>
-   * Excludes the actual bind values (as they don't effect the query plan).
-   * </p>
-   */
-  HashQueryPlan queryPlanHash(BeanQueryRequest<?> request);
+  CQueryPlanKey prepare(BeanQueryRequest<?> request);
 
   /**
    * Calculate a hash based on the bind values used in the query.

src/main/java/com/avaje/ebeaninternal/api/SpiQuerySecondary.java

@@ -0,0 +1,21 @@
+package com.avaje.ebeaninternal.api;
+
+import com.avaje.ebeaninternal.server.querydefn.OrmQueryProperties;
+
+import java.util.List;
+
+/**
+ * The secondary query paths for 'query joins' and 'lazy loading'.
+ */
+public interface SpiQuerySecondary {
+
+  /**
+   * Return a list of path/properties that are query join loaded.
+   */
+  List<OrmQueryProperties> getQueryJoins();
+
+  /**
+   * Return the list of path/properties that are lazy loaded.
+   */
+  List<OrmQueryProperties> getLazyJoins();
+}

src/main/java/com/avaje/ebeaninternal/server/autotune/service/ProfileOrigin.java

@@ -110,7 +110,7 @@ public class ProfileOrigin {
     Collection<Props> pathProperties = pathProps.getPathProps();
     for (Props props : pathProperties) {
       if (!props.isEmpty()) {
-        detail.addFetch(props.getPath(), props.getPropertiesAsString(), null);
+        detail.fetch(props.getPath(), props.getPropertiesAsString(), null);
       }
     }
 

src/main/java/com/avaje/ebeaninternal/server/core/DefaultServer.java

@@ -15,7 +15,6 @@ import com.avaje.ebean.config.ServerConfig;
 import com.avaje.ebean.config.dbplatform.DatabasePlatform;
 import com.avaje.ebean.dbmigration.DdlGenerator;
 import com.avaje.ebean.event.BeanPersistController;
-import com.avaje.ebean.event.BeanQueryAdapter;
 import com.avaje.ebean.event.readaudit.ReadAuditLogger;
 import com.avaje.ebean.event.readaudit.ReadAuditPrepare;
 import com.avaje.ebean.meta.MetaInfoManager;
@@ -32,7 +31,6 @@ import com.avaje.ebeaninternal.api.SpiBackgroundExecutor;
 import com.avaje.ebeaninternal.api.SpiEbeanPlugin;
 import com.avaje.ebeaninternal.api.SpiEbeanServer;
 import com.avaje.ebeaninternal.api.SpiQuery;
-import com.avaje.ebeaninternal.api.SpiQuery.Mode;
 import com.avaje.ebeaninternal.api.SpiQuery.Type;
 import com.avaje.ebeaninternal.api.SpiSqlQuery;
 import com.avaje.ebeaninternal.api.SpiTransaction;
@@ -463,19 +461,10 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
     return cqueryEngine.buildQuery(orm);
   }
 
-  public CQueryEngine getQueryEngine() {
-    return cqueryEngine;
-  }
-
   public ServerCacheManager getServerCacheManager() {
     return serverCacheManager;
   }
 
-  public void refreshMany(Object parentBean, String propertyName, Transaction t) {
-
-    beanLoader.refreshMany(checkEntityBean(parentBean), propertyName, t);
-  }
-
   public void refreshMany(Object parentBean, String propertyName) {
 
     beanLoader.refreshMany(checkEntityBean(parentBean), propertyName);
@@ -1048,7 +1037,7 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
     return findId(query, t);
   }
 
-  private <T> SpiOrmQueryRequest<T> createQueryRequest(Type type, Query<T> query, Transaction t) {
+  <T> SpiOrmQueryRequest<T> createQueryRequest(Type type, Query<T> query, Transaction t) {
 
     SpiQuery<T> spiQuery = (SpiQuery<T>) query;
     spiQuery.setType(type);
@@ -1059,7 +1048,7 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
     return createQueryRequest(desc, spiQuery, t);
   }
 
-  public <T> SpiOrmQueryRequest<T> createQueryRequest(BeanDescriptor<T> desc, SpiQuery<T> query, Transaction t) {
+  private <T> SpiOrmQueryRequest<T> createQueryRequest(BeanDescriptor<T> desc, SpiQuery<T> query, Transaction t) {
 
     if (desc.isAutoTunable() && !query.isSqlSelect() && !autoTuneService.tuneQuery(query)) {
       // use deployment FetchType.LAZY/EAGER annotations
@@ -1067,50 +1056,15 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
       query.setDefaultSelectClause();
     }
 
-    if (query.selectAllForLazyLoadProperty()) {
-      // we need to select all properties to ensure the lazy load property
-      // was included (was not included by default or via autoTune).
-      if (logger.isDebugEnabled()) {
-        logger.debug("Using selectAllForLazyLoadProperty");
-      }
-    }
+    query.selectAllForLazyLoadProperty();
 
     // if determine cost and no origin for AutoTune
     if (query.getParentNode() == null) {
       query.setOrigin(createCallStack());
     }
 
-    // determine extra joins required to support where clause
-    // predicates on *ToMany properties
-    if (query.initManyWhereJoins()) {
-      // we need a sql distinct now
-      query.setSqlDistinct(true);
-    }
-
-    boolean allowOneManyFetch = true;
-    if (Mode.LAZYLOAD_MANY.equals(query.getMode())) {
-      allowOneManyFetch = false;
-
-    } else if (query.hasMaxRowsOrFirstRow() && !query.isRawSql() && !query.isSqlSelect()) {
-      // convert ALL fetch joins to Many's to be query joins
-      // so that limit offset type SQL clauses work
-      allowOneManyFetch = false;
-    }
-
-    query.convertManyFetchJoinsToQueryJoins(allowOneManyFetch, queryBatchSize);
-
-    SpiTransaction serverTrans = (SpiTransaction) t;
-    OrmQueryRequest<T> request = new OrmQueryRequest<T>(this, queryEngine, query, desc, serverTrans);
-
-    BeanQueryAdapter queryAdapter = desc.getQueryAdapter();
-    if (queryAdapter != null) {
-      // adaption of the query probably based on the
-      // current user
-      queryAdapter.preQuery(request);
-    }
-
-    // the query hash after any tuning
-    request.calculateQueryPlanHash();
+    OrmQueryRequest<T> request = new OrmQueryRequest<T>(this, queryEngine, query, desc, (SpiTransaction) t);
+    request.prepareQuery();
 
     return request;
   }

src/main/java/com/avaje/ebeaninternal/server/core/OrmQueryRequest.java

@@ -1,26 +1,25 @@
 package com.avaje.ebeaninternal.server.core;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
-import javax.persistence.PersistenceException;
-
-import com.avaje.ebean.*;
+import com.avaje.ebean.PersistenceContextScope;
+import com.avaje.ebean.QueryEachConsumer;
+import com.avaje.ebean.QueryEachWhileConsumer;
+import com.avaje.ebean.QueryIterator;
+import com.avaje.ebean.RawSql;
+import com.avaje.ebean.Version;
 import com.avaje.ebean.bean.BeanCollection;
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebean.bean.PersistenceContext;
 import com.avaje.ebean.event.BeanFindController;
+import com.avaje.ebean.event.BeanQueryAdapter;
 import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.BeanIdList;
+import com.avaje.ebeaninternal.api.CQueryPlanKey;
 import com.avaje.ebeaninternal.api.HashQuery;
-import com.avaje.ebeaninternal.api.HashQueryPlan;
 import com.avaje.ebeaninternal.api.LoadContext;
 import com.avaje.ebeaninternal.api.SpiEbeanServer;
 import com.avaje.ebeaninternal.api.SpiQuery;
 import com.avaje.ebeaninternal.api.SpiQuery.Type;
+import com.avaje.ebeaninternal.api.SpiQuerySecondary;
 import com.avaje.ebeaninternal.api.SpiTransaction;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
@@ -32,6 +31,13 @@ import com.avaje.ebeaninternal.server.query.CQueryPlan;
 import com.avaje.ebeaninternal.server.query.CancelableQuery;
 import com.avaje.ebeaninternal.server.transaction.DefaultPersistenceContext;
 
+import javax.persistence.PersistenceException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
 /**
  * Wraps the objects involved in executing a Query.
  */
@@ -55,7 +61,9 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
 
   private HashQuery cacheKey;
 
-  private HashQueryPlan queryPlanHash;
+  private CQueryPlanKey queryPlanKey;
+
+  private SpiQuerySecondary secondaryQueries;
 
   /**
    * Create the InternalQueryRequest.
@@ -126,10 +134,24 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
   }
 
   /**
-   * Calculate the query plan hash AFTER any potential AutoTune tuning.
+   * Run BeanQueryAdapter preQuery() if needed.
    */
-  public void calculateQueryPlanHash() {
-    this.queryPlanHash = query.queryPlanHash(this);
+  private void adapterPreQuery() {
+    BeanQueryAdapter queryAdapter = beanDescriptor.getQueryAdapter();
+    if (queryAdapter != null) {
+      queryAdapter.preQuery(this);
+    }
+  }
+
+  /**
+   * Prepare the query and calculate the query plan key.
+   */
+  public void prepareQuery() {
+
+    adapterPreQuery();
+
+    this.secondaryQueries = query.convertJoins();
+    this.queryPlanKey = query.prepare(this);
   }
 
   public boolean isRawSql() {
@@ -190,8 +212,7 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
     }
     // initialise the persistenceContext and loadContext
     this.persistenceContext = getPersistenceContext(query, transaction);
-    this.loadContext = new DLoadContext(this);
-    this.loadContext.registerSecondaryQueries(query);
+    this.loadContext = new DLoadContext(this, secondaryQueries);
   }
 
   /**
@@ -215,7 +236,7 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
 
     // determine the scope (from the query and then server)
     PersistenceContextScope scope = ebeanServer.getPersistenceContextScope(query);
-    return (scope == PersistenceContextScope.QUERY) ? new DefaultPersistenceContext() :  t.getPersistenceContext();
+    return (scope == PersistenceContextScope.QUERY) ? new DefaultPersistenceContext() : t.getPersistenceContext();
   }
 
   /**
@@ -305,7 +326,7 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
    */
   @SuppressWarnings("unchecked")
   public Set<?> findSet() {
-    return (Set<T>)queryEngine.findMany(this);
+    return (Set<T>) queryEngine.findMany(this);
   }
 
   /**
@@ -324,10 +345,6 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
     return (Map<?, ?>) queryEngine.findMany(this);
   }
 
-  public SpiQuery.Type getQueryType() {
-    return query.getType();
-  }
-
   /**
    * Return a bean specific finder if one has been set.
    */
@@ -355,7 +372,7 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
    * query plan for this query exists.
    */
   public CQueryPlan getQueryPlan() {
-    return beanDescriptor.getQueryPlan(queryPlanHash);
+    return beanDescriptor.getQueryPlan(queryPlanKey);
   }
 
   /**
@@ -366,15 +383,15 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
    * with just the bind variables changing.
    * </p>
    */
-  public HashQueryPlan getQueryPlanHash() {
-    return queryPlanHash;
+  public CQueryPlanKey getQueryPlanKey() {
+    return queryPlanKey;
   }
 
   /**
    * Put the QueryPlan into the cache.
    */
   public void putQueryPlan(CQueryPlan queryPlan) {
-    beanDescriptor.putQueryPlan(queryPlanHash, queryPlan);
+    beanDescriptor.putQueryPlan(queryPlanKey, queryPlan);
   }
 
   public boolean isUseBeanCache() {
@@ -401,7 +418,7 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
       for (T bean : actualDetails) {
         ids.add(beanDescriptor.getIdForJson(bean));
       }
-      beanDescriptor.readAuditMany(queryPlanHash.getPartialKey(), "l2-query-cache", ids);
+      beanDescriptor.readAuditMany(queryPlanKey.getPartialKey(), "l2-query-cache", ids);
     }
 
     return cached;

src/main/java/com/avaje/ebeaninternal/server/deploy/BeanCollectionHelp.java

@@ -42,7 +42,7 @@ public interface BeanCollectionHelp<T> {
 	/**
 	 * Add a bean to the List Set or Map.
 	 */
-	void add(BeanCollection<?> collection, EntityBean bean);
+	void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck);
 
 	/**
 	 * Create a lazy loading proxy for a List Set or Map.

src/main/java/com/avaje/ebeaninternal/server/deploy/BeanDescriptor.java

@@ -29,7 +29,7 @@ import com.avaje.ebean.event.readaudit.ReadEvent;
 import com.avaje.ebean.meta.MetaBeanInfo;
 import com.avaje.ebean.meta.MetaQueryPlanStatistic;
 import com.avaje.ebean.plugin.SpiBeanType;
-import com.avaje.ebeaninternal.api.HashQueryPlan;
+import com.avaje.ebeaninternal.api.CQueryPlanKey;
 import com.avaje.ebeaninternal.api.SpiEbeanServer;
 import com.avaje.ebeaninternal.api.SpiQuery;
 import com.avaje.ebeaninternal.api.SpiTransaction;
@@ -73,9 +73,9 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
 
 /**
@@ -87,7 +87,7 @@ public class BeanDescriptor<T> implements MetaBeanInfo, SpiBeanType<T> {
 
   private final ConcurrentHashMap<Integer, SpiUpdatePlan> updatePlanCache = new ConcurrentHashMap<Integer, SpiUpdatePlan>();
 
-  private final ConcurrentHashMap<HashQueryPlan, CQueryPlan> queryPlanCache = new ConcurrentHashMap<HashQueryPlan, CQueryPlan>();
+  private final ConcurrentHashMap<CQueryPlanKey, CQueryPlan> queryPlanCache = new ConcurrentHashMap<CQueryPlanKey, CQueryPlan>();
 
   private final ConcurrentHashMap<String, ElPropertyValue> elCache = new ConcurrentHashMap<String, ElPropertyValue>();
 
@@ -347,7 +347,7 @@ public class BeanDescriptor<T> implements MetaBeanInfo, SpiBeanType<T> {
   private final BeanDescriptorJsonHelp<T> jsonHelp;
   
   private final String defaultSelectClause;
-  private final Set<String> defaultSelectClauseSet;
+  private final LinkedHashSet<String> defaultSelectClauseSet;
 
   private SpiEbeanServer ebeanServer;
 
@@ -856,7 +856,7 @@ public class BeanDescriptor<T> implements MetaBeanInfo, SpiBeanType<T> {
   /**
    * Return the default select clause already parsed into an ordered Set.
    */
-  public Set<String> getDefaultSelectClauseSet() {
+  public LinkedHashSet<String> getDefaultSelectClauseSet() {
     return defaultSelectClauseSet;
   }
 
@@ -1163,11 +1163,11 @@ public class BeanDescriptor<T> implements MetaBeanInfo, SpiBeanType<T> {
     }
   }
 
-  public CQueryPlan getQueryPlan(HashQueryPlan key) {
+  public CQueryPlan getQueryPlan(CQueryPlanKey key) {
     return queryPlanCache.get(key);
   }
 
-  public void putQueryPlan(HashQueryPlan key, CQueryPlan plan) {
+  public void putQueryPlan(CQueryPlanKey key, CQueryPlan plan) {
     queryPlanCache.put(key, plan);
   }
 
@@ -1252,7 +1252,7 @@ public class BeanDescriptor<T> implements MetaBeanInfo, SpiBeanType<T> {
 
     OrmQueryDetail detail = query.getDetail();
     for (int i = 0; i < propertiesMany.length; i++) {
-      if (detail.includes(propertiesMany[i].getName())) {
+      if (detail.includesPath(propertiesMany[i].getName())) {
         return propertiesMany[i];
       }
     }

src/main/java/com/avaje/ebeaninternal/server/deploy/BeanListHelp.java

@@ -46,8 +46,12 @@ public final class BeanListHelp<T> implements BeanCollectionHelp<T> {
    * Internal add bypassing any modify listening.
    */
   @Override
-  public void add(BeanCollection<?> collection, EntityBean bean) {
-    collection.internalAdd(bean);
+  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
+    if (withCheck) {
+      collection.internalAddWithCheck(bean);
+    } else {
+      collection.internalAdd(bean);
+    }
   }
 
   @Override

src/main/java/com/avaje/ebeaninternal/server/deploy/BeanMapHelp.java

@@ -108,13 +108,14 @@ public final class BeanMapHelp<T> implements BeanCollectionHelp<T> {
   }
 
   @Override
-  public void add(BeanCollection<?> collection, EntityBean bean) {
+  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
 
     if (bean == null) {
       ((BeanMap<?, ?>) collection).internalPutNull();
     } else {
       Object keyValue = beanProperty.getValueIntercept(bean);
-      ((BeanMap<?, ?>) collection).internalPut(keyValue, bean);
+      BeanMap<?, ?> map = ((BeanMap<?, ?>) collection);
+      map.internalPutWithCheck(keyValue, bean);
     }
   }
 

src/main/java/com/avaje/ebeaninternal/server/deploy/BeanPropertyAssocMany.java

@@ -182,13 +182,13 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
   /**
    * Add the bean to the appropriate collection on the parent bean.
    */
-  public void addBeanToCollectionWithCreate(EntityBean parentBean, EntityBean detailBean) {
+  public void addBeanToCollectionWithCreate(EntityBean parentBean, EntityBean detailBean, boolean withCheck) {
     BeanCollection<?> bc = (BeanCollection<?>) super.getValue(parentBean);
     if (bc == null) {
       bc = help.createEmpty(parentBean);
       setValue(parentBean, bc);
     }
-    help.add(bc, detailBean);
+    help.add(bc, detailBean, withCheck);
   }
 
   /**
@@ -416,7 +416,7 @@ public class BeanPropertyAssocMany<T> extends BeanPropertyAssoc<T> {
   }
 
   public void add(BeanCollection<?> collection, EntityBean bean) {
-    help.add(collection, bean);
+    help.add(collection, bean, false);
   }
 
   /**

src/main/java/com/avaje/ebeaninternal/server/deploy/BeanSetHelp.java

@@ -61,8 +61,12 @@ public final class BeanSetHelp<T> implements BeanCollectionHelp<T> {
     }
   }
 
-  public void add(BeanCollection<?> collection, EntityBean bean) {
-    collection.internalAdd(bean);
+  public void add(BeanCollection<?> collection, EntityBean bean, boolean withCheck) {
+    if (withCheck) {
+      collection.internalAddWithCheck(bean);
+    } else {
+      collection.internalAdd(bean);
+    }
   }
 
   @Override

src/main/java/com/avaje/ebeaninternal/server/deploy/IntersectionRow.java

@@ -2,6 +2,7 @@ package com.avaje.ebeaninternal.server.deploy;
 
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
+import java.util.List;
 import java.util.Map;
 
 import com.avaje.ebean.EbeanServer;
@@ -9,7 +10,7 @@ import com.avaje.ebean.SqlUpdate;
 import com.avaje.ebeaninternal.api.BindParams;
 import com.avaje.ebeaninternal.server.core.DefaultSqlUpdate;
 import com.avaje.ebeaninternal.server.expression.IdInExpression;
-import com.avaje.ebeaninternal.util.DefaultExpressionRequest;
+import com.avaje.ebeaninternal.server.expression.DefaultExpressionRequest;
 
 public class IntersectionRow {
 
@@ -98,7 +99,7 @@ public class IntersectionRow {
       sb.append(er.getSql());
       sb.append(" ) ");
 
-      ArrayList<Object> bindValues = er.getBindValues();
+      List<Object> bindValues = er.getBindValues();
       for (int i = 0; i < bindValues.size(); i++) {
         bindParams.setParameter(++count, bindValues.get(i));
       }

src/main/java/com/avaje/ebeaninternal/server/deploy/TableJoin.java

@@ -63,6 +63,32 @@ public final class TableJoin {
     return hc;
   }
 
+  @Override
+  public int hashCode() {
+    return queryHash;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+
+    TableJoin that = (TableJoin) o;
+
+    if (!table.equals(that.table)) return false;
+    if (type != that.type) return false;
+    if (columns.length != that.columns.length) return false;
+
+    for (int i = 0; i < columns.length; i++) {
+      if (!columns[i].equals(that.columns[i])) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+
+
   /**
    * Return a hash value for adding to a query plan.
    */

src/main/java/com/avaje/ebeaninternal/server/deploy/TableJoinColumn.java

@@ -8,76 +8,97 @@ import com.avaje.ebeaninternal.server.deploy.meta.DeployTableJoinColumn;
  */
 public class TableJoinColumn {
 
-    /**
-     * The local database column name.
-     */
-    private final String localDbColumn;
+  /**
+   * The local database column name.
+   */
+  private final String localDbColumn;
 
-    /**
-     * The foreign database column name.
-     */
-    private final String foreignDbColumn;
+  /**
+   * The foreign database column name.
+   */
+  private final String foreignDbColumn;
 
-    private final boolean insertable;
-    
-    private final boolean updateable;
+  private final boolean insertable;
 
-    /**
-     * Hash for including in a query plan
-     */
-    private final int queryHash;
+  private final boolean updateable;
 
-    /**
-     * Create the pair.
-     */
-    public TableJoinColumn(DeployTableJoinColumn deploy) {
-    	this.localDbColumn = InternString.intern(deploy.getLocalDbColumn());
-    	this.foreignDbColumn = InternString.intern(deploy.getForeignDbColumn());
-    	this.insertable = deploy.isInsertable();
-    	this.updateable = deploy.isUpdateable();
-      this.queryHash = hashOf(localDbColumn) * 31 + hashOf(foreignDbColumn);
-    }
+  /**
+   * Hash for including in a query plan
+   */
+  private final int queryHash;
 
-    private int hashOf(String value) {
-        return (value == null) ? 0 : value.hashCode();
-    }
+  /**
+   * Create the pair.
+   */
+  public TableJoinColumn(DeployTableJoinColumn deploy) {
+    this.localDbColumn = InternString.intern(deploy.getLocalDbColumn());
+    this.foreignDbColumn = InternString.intern(deploy.getForeignDbColumn());
+    this.insertable = deploy.isInsertable();
+    this.updateable = deploy.isUpdateable();
+    this.queryHash = hash();
+  }
 
-    public String toString() {
-        return localDbColumn+" = "+foreignDbColumn;
-    }
+  int hash() {
+    int result = localDbColumn != null ? localDbColumn.hashCode() : 0;
+    result = 31 * result + (foreignDbColumn != null ? foreignDbColumn.hashCode() : 0);
+    result = 31 * result + (insertable ? 1 : 0);
+    result = 31 * result + (updateable ? 1 : 0);
+    return result;
+  }
 
-    /**
-     * Return a hash for including in a query plan.
-     */
-    public int queryHash() {
-      return queryHash;
-    }
+  @Override
+  public int hashCode() {
+    return queryHash;
+  }
 
-    /**
-     * Return the foreign database column name.
-     */
-    public String getForeignDbColumn() {
-        return foreignDbColumn;
-    }
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
 
-    /**
-     * Return the local database column name.
-     */
-    public String getLocalDbColumn() {
-        return localDbColumn;
-    }
+    TableJoinColumn that = (TableJoinColumn) o;
+    if (insertable != that.insertable) return false;
+    if (updateable != that.updateable) return false;
+    if (!localDbColumn.equals(that.localDbColumn)) return false;
+    return foreignDbColumn.equals(that.foreignDbColumn);
+  }
 
-	/**
-	 * Return true if this column should be insertable.
-	 */
-	public boolean isInsertable() {
-		return insertable;
-	}
+  public String toString() {
+    return localDbColumn + " = " + foreignDbColumn;
+  }
 
-	/**
-	 * Return true if this column should be updateable.
-	 */
-	public boolean isUpdateable() {
-		return updateable;
-	}
+  /**
+   * Return a hash for including in a query plan.
+   */
+  public int queryHash() {
+    return queryHash;
+  }
+
+  /**
+   * Return the foreign database column name.
+   */
+  public String getForeignDbColumn() {
+    return foreignDbColumn;
+  }
+
+  /**
+   * Return the local database column name.
+   */
+  public String getLocalDbColumn() {
+    return localDbColumn;
+  }
+
+  /**
+   * Return true if this column should be insertable.
+   */
+  public boolean isInsertable() {
+    return insertable;
+  }
+
+  /**
+   * Return true if this column should be updateable.
+   */
+  public boolean isUpdateable() {
+    return updateable;
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/CounterFactory.java

@@ -1,13 +1,12 @@
 package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
+import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanProperty;
+
+import javax.persistence.PersistenceException;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.sql.Types;
 
-import javax.persistence.PersistenceException;
-
-import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanProperty;
-
 /**
  * Creates "Counter" GeneratedProperty for various types of number.
  * <p>
@@ -16,49 +15,49 @@ import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanProperty;
  */
 public class CounterFactory {
 
-	final GeneratedCounterInteger integerCounter = new GeneratedCounterInteger();
+  final GeneratedCounterInteger integerCounter = new GeneratedCounterInteger();
 
-	final GeneratedCounterLong longCounter = new GeneratedCounterLong();
+  final GeneratedCounterLong longCounter = new GeneratedCounterLong();
 
-	public void setCounter(DeployBeanProperty property) {
+  public void setCounter(DeployBeanProperty property) {
 
-		property.setGeneratedProperty(createCounter(property));
-	}
-	
-	/**
-	 * Create the GeneratedProperty based on the property type.
-	 */
-	private GeneratedProperty createCounter(DeployBeanProperty property) {
-		
-		Class<?> propType = property.getPropertyType();
-		if (propType.equals(Integer.class) || propType.equals(int.class)) {
-			return integerCounter;
-		}
-		if (propType.equals(Long.class) || propType.equals(long.class)) {
-			return longCounter;
-		}
-		
-		int type = getType(propType);
-		return new GeneratedCounter(type);
-	}
-	
-	private int getType(Class<?> propType){
-		if (propType.equals(Short.class) || propType.equals(short.class)){
-			return Types.TINYINT;
-		}
-		if (propType.equals(BigDecimal.class)){
-			return Types.DECIMAL;
-		}
-		if (propType.equals(Double.class) || propType.equals(double.class)){
-			return Types.DOUBLE;
-		}
-		if (propType.equals(Float.class) || propType.equals(float.class)){
-			return Types.REAL;
-		}
-		if (propType.equals(BigInteger.class)){
-			return Types.BIGINT;
-		}
-		String msg = "Can not support Counter for type "+propType.getName();
-		throw new PersistenceException(msg);
-	}
+    property.setGeneratedProperty(createCounter(property));
+  }
+
+  /**
+   * Create the GeneratedProperty based on the property type.
+   */
+  private GeneratedProperty createCounter(DeployBeanProperty property) {
+
+    Class<?> propType = property.getPropertyType();
+    if (propType.equals(Integer.class) || propType.equals(int.class)) {
+      return integerCounter;
+    }
+    if (propType.equals(Long.class) || propType.equals(long.class)) {
+      return longCounter;
+    }
+
+    int type = getType(propType);
+    return new GeneratedCounter(type);
+  }
+
+  private int getType(Class<?> propType) {
+    if (propType.equals(Short.class) || propType.equals(short.class)) {
+      return Types.TINYINT;
+    }
+    if (propType.equals(BigDecimal.class)) {
+      return Types.DECIMAL;
+    }
+    if (propType.equals(Double.class) || propType.equals(double.class)) {
+      return Types.DOUBLE;
+    }
+    if (propType.equals(Float.class) || propType.equals(float.class)) {
+      return Types.REAL;
+    }
+    if (propType.equals(BigInteger.class)) {
+      return Types.BIGINT;
+    }
+    String msg = "Can not support Counter for type " + propType.getName();
+    throw new PersistenceException(msg);
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedCounter.java

@@ -9,49 +9,51 @@ import com.avaje.ebeaninternal.server.deploy.BeanProperty;
  */
 public class GeneratedCounter implements GeneratedProperty {
 
-    final int numberType;
+  final int numberType;
 
-    public GeneratedCounter(int numberType) {
-        this.numberType = numberType;
-    }
+  public GeneratedCounter(int numberType) {
+    this.numberType = numberType;
+  }
 
-    /**
-     * Always returns a 1.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return BasicTypeConverter.convert(1, numberType);
-    }
+  /**
+   * Always returns a 1.
+   */
+  @Override
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return BasicTypeConverter.convert(1, numberType);
+  }
 
-    /**
-     * Increments the current value by one.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        Number currVal = (Number) prop.getValue(bean);
-        Integer nextVal = currVal.intValue() + 1;
-        return BasicTypeConverter.convert(nextVal, numberType);
-    }
+  /**
+   * Increments the current value by one.
+   */
+  @Override
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    Number currVal = (Number) prop.getValue(bean);
+    Integer nextVal = currVal.intValue() + 1;
+    return BasicTypeConverter.convert(nextVal, numberType);
+  }
 
-    /**
-     * Include this in every update.
-     */
-    public boolean includeInUpdate() {
-        return true;
-    }
+  /**
+   * Include this in every update.
+   */
+  public boolean includeInUpdate() {
+    return true;
+  }
 
-    @Override
-    public boolean includeInAllUpdates() {
-      return false;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return false;
+  }
 
-    /**
-     * Include this in every insert setting initial counter value to 1.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  /**
+   * Include this in every insert setting initial counter value to 1.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedCounterInteger.java

@@ -8,46 +8,48 @@ import com.avaje.ebeaninternal.server.deploy.BeanProperty;
  */
 public class GeneratedCounterInteger implements GeneratedProperty {
 
-    public GeneratedCounterInteger() {
+  public GeneratedCounterInteger() {
 
-    }
+  }
 
-    /**
-     * Always returns a 1.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return 1;
-    }
+  /**
+   * Always returns a 1.
+   */
+  @Override
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return 1;
+  }
 
-    /**
-     * Increments the current value by one.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        Integer i = (Integer) prop.getValue(bean);
-        return i + 1;
-    }
+  /**
+   * Increments the current value by one.
+   */
+  @Override
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    Integer i = (Integer) prop.getValue(bean);
+    return i + 1;
+  }
 
-    /**
-     * Include this in every update.
-     */
-    public boolean includeInUpdate() {
-        return true;
-    }
-    
-    @Override
-    public boolean includeInAllUpdates() {
-      return false;
-    }
+  /**
+   * Include this in every update.
+   */
+  public boolean includeInUpdate() {
+    return true;
+  }
 
-    /**
-     * Include this in every insert setting initial counter value to 1.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return false;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  /**
+   * Include this in every insert setting initial counter value to 1.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
+
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedCounterLong.java

@@ -8,46 +8,48 @@ import com.avaje.ebeaninternal.server.deploy.BeanProperty;
  */
 public class GeneratedCounterLong implements GeneratedProperty {
 
-    public GeneratedCounterLong() {
+  public GeneratedCounterLong() {
 
-    }
+  }
 
-    /**
-     * Always returns a 1.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return (long) 1;
-    }
+  /**
+   * Always returns a 1.
+   */
+  @Override
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return (long) 1;
+  }
 
-    /**
-     * Increments the current value by one.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        Long i = (Long) prop.getValue(bean);
-        return i + 1;
-    }
+  /**
+   * Increments the current value by one.
+   */
+  @Override
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    Long i = (Long) prop.getValue(bean);
+    return i + 1;
+  }
 
-    /**
-     * Include this in every update.
-     */
-    public boolean includeInUpdate() {
-        return true;
-    }
+  /**
+   * Include this in every update.
+   */
+  public boolean includeInUpdate() {
+    return true;
+  }
 
-    @Override
-    public boolean includeInAllUpdates() {
-      return false;
-    }
-    
-    /**
-     * Include this in every insert setting initial counter value to 1.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return false;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  /**
+   * Include this in every insert setting initial counter value to 1.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
+
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedInsertDate.java

@@ -1,50 +1,52 @@
 package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
-import java.util.Date;
-
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
 
+import java.util.Date;
+
 /**
  * Used to generate a (java.util.Date) timestamp when a bean is inserted.
  */
 public class GeneratedInsertDate implements GeneratedProperty {
 
-    /**
-     * Return the current time as a Timestamp.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return new Date(System.currentTimeMillis());
-    }
+  /**
+   * Return the current time as a Timestamp.
+   */
+  @Override
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return new Date(now);
+  }
 
-    /**
-     * Just returns the beans original insert timestamp value.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        return prop.getValue(bean);
-    }
+  /**
+   * Just returns the beans original insert timestamp value.
+   */
+  @Override
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    return prop.getValue(bean);
+  }
 
-    /**
-     * Return false.
-     */
-    public boolean includeInUpdate() {
-        return false;
-    }
+  /**
+   * Return false.
+   */
+  public boolean includeInUpdate() {
+    return false;
+  }
 
-    @Override
-    public boolean includeInAllUpdates() {
-      return false;
-    }
-    
-    /**
-     * Return true.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return false;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  /**
+   * Return true.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
+
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedInsertJavaTime.java

@@ -3,10 +3,6 @@ package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
 
-import java.time.LocalDateTime;
-import java.time.OffsetDateTime;
-import java.time.ZonedDateTime;
-
 /**
  * Support java.time types as GeneratedProperty.
  */
@@ -35,7 +31,7 @@ public class GeneratedInsertJavaTime {
     }
 
     @Override
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
+    public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
       return prop.getValue(bean);
     }
   }
@@ -46,8 +42,8 @@ public class GeneratedInsertJavaTime {
   public static class LocalDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return LocalDateTime.now();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toLocalDateTime(now);
     }
   }
 
@@ -57,8 +53,8 @@ public class GeneratedInsertJavaTime {
   public static class OffsetDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return OffsetDateTime.now();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toOffsetDateTime(now);
     }
 
   }
@@ -69,8 +65,8 @@ public class GeneratedInsertJavaTime {
   public static class ZonedDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return ZonedDateTime.now();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toZonedDateTime(now);
     }
 
   }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedInsertJodaTime.java

@@ -2,9 +2,8 @@ package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
-
-import org.joda.time.LocalDateTime;
 import org.joda.time.DateTime;
+import org.joda.time.LocalDateTime;
 
 /**
  * Support joda time types as GeneratedProperty.
@@ -34,7 +33,7 @@ public class GeneratedInsertJodaTime {
     }
 
     @Override
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
+    public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
       return prop.getValue(bean);
     }
   }
@@ -45,8 +44,8 @@ public class GeneratedInsertJodaTime {
   public static class LocalDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return new LocalDateTime();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return new LocalDateTime(now);
     }
   }
 
@@ -56,8 +55,8 @@ public class GeneratedInsertJodaTime {
   public static class DateTimeDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return new DateTime();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return new DateTime(now);
     }
 
   }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedInsertLong.java

@@ -8,41 +8,43 @@ import com.avaje.ebeaninternal.server.deploy.BeanProperty;
  */
 public class GeneratedInsertLong implements GeneratedProperty {
 
-    /**
-     * Return the current time as a Timestamp.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return System.currentTimeMillis();
-    }
+  /**
+   * Return the current time as a Timestamp.
+   */
+  @Override
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return now;
+  }
 
-    /**
-     * Just returns the beans original insert timestamp value.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        return prop.getValue(bean);
-    }
+  /**
+   * Just returns the beans original insert timestamp value.
+   */
+  @Override
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    return prop.getValue(bean);
+  }
 
-    /**
-     * Return false.
-     */
-    public boolean includeInUpdate() {
-        return false;
-    }
+  /**
+   * Return false.
+   */
+  public boolean includeInUpdate() {
+    return false;
+  }
 
-    @Override
-    public boolean includeInAllUpdates() {
-      return false;
-    }
-    
-    /**
-     * Return true.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return false;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  /**
+   * Return true.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
+
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedInsertTimestamp.java

@@ -1,50 +1,52 @@
 package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
-import java.sql.Timestamp;
-
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
 
+import java.sql.Timestamp;
+
 /**
  * Used to generate a timestamp when a bean is inserted.
  */
 public class GeneratedInsertTimestamp implements GeneratedProperty, GeneratedWhenCreated {
 
-    /**
-     * Return the current time as a Timestamp.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return new Timestamp(System.currentTimeMillis());
-    }
+  /**
+   * Return the current time as a Timestamp.
+   */
+  @Override
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return new Timestamp(now);
+  }
 
-    /**
-     * Just returns the beans original insert timestamp value.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        return prop.getValue(bean);
-    }
+  /**
+   * Just returns the beans original insert timestamp value.
+   */
+  @Override
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    return prop.getValue(bean);
+  }
 
-    /**
-     * Return false.
-     */
-    public boolean includeInUpdate() {
-        return false;
-    }
-    
-    @Override
-    public boolean includeInAllUpdates() {
-      return false;
-    }
+  /**
+   * Return false.
+   */
+  public boolean includeInUpdate() {
+    return false;
+  }
 
-    /**
-     * Return true.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return false;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  /**
+   * Return true.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
+
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedProperty.java

@@ -9,39 +9,39 @@ import com.avaje.ebeaninternal.server.deploy.BeanProperty;
  */
 public interface GeneratedProperty {
 
-    /**
-     * Get the generated insert value for a specific property of a bean.
-     */
-    Object getInsertValue(BeanProperty prop, EntityBean bean);
+  /**
+   * Get the generated insert value for a specific property of a bean.
+   */
+  Object getInsertValue(BeanProperty prop, EntityBean bean, long now);
 
-    /**
-     * Get the generated update value for a specific property of a bean.
-     */
-    Object getUpdateValue(BeanProperty prop, EntityBean bean);
+  /**
+   * Get the generated update value for a specific property of a bean.
+   */
+  Object getUpdateValue(BeanProperty prop, EntityBean bean, long now);
 
-    /**
-     * Return true if this should always be includes in an update statement.
-     * <p>
-     * Used to include GeneratedUpdateTimestamp in dynamic table updates.
-     * </p>
-     */
-    boolean includeInUpdate();
-    
-    /**
-     * Return true if the property should be included in an update even if
-     * it is not loaded (ie. Last Updated Timestamp).
-     */
-    boolean includeInAllUpdates();
+  /**
+   * Return true if this should always be includes in an update statement.
+   * <p>
+   * Used to include GeneratedUpdateTimestamp in dynamic table updates.
+   * </p>
+   */
+  boolean includeInUpdate();
 
-    /**
-     * Return true if this should be included in insert statements.
-     */
-    boolean includeInInsert();
+  /**
+   * Return true if the property should be included in an update even if
+   * it is not loaded (ie. Last Updated Timestamp).
+   */
+  boolean includeInAllUpdates();
 
-    /**
-     * Return true if the GeneratedProperty implies the DDL to create the DB
-     * column should have a not null constraint.
-     */
-    boolean isDDLNotNullable();
+  /**
+   * Return true if this should be included in insert statements.
+   */
+  boolean includeInInsert();
+
+  /**
+   * Return true if the GeneratedProperty implies the DDL to create the DB
+   * column should have a not null constraint.
+   */
+  boolean isDDLNotNullable();
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedPropertyFactory.java

@@ -1,19 +1,19 @@
 package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
-import java.math.BigDecimal;
-import java.util.HashSet;
-
 import com.avaje.ebean.config.ClassLoadConfig;
 import com.avaje.ebean.config.CurrentUserProvider;
 import com.avaje.ebean.config.ServerConfig;
 import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanProperty;
 
+import java.math.BigDecimal;
+import java.util.HashSet;
+
 /**
  * Default implementation of GeneratedPropertyFactory.
  */
 public class GeneratedPropertyFactory {
 
-	private final CounterFactory counterFactory = new CounterFactory();
+  private final CounterFactory counterFactory = new CounterFactory();
 
   private final InsertTimestampFactory insertFactory;
 
@@ -34,7 +34,7 @@ public class GeneratedPropertyFactory {
     this.updateFactory = new UpdateTimestampFactory(classLoadConfig);
 
     CurrentUserProvider currentUserProvider = serverConfig.getCurrentUserProvider();
-	  if (currentUserProvider != null) {
+    if (currentUserProvider != null) {
       generatedWhoCreated = new GeneratedWhoCreated(currentUserProvider);
       generatedWhoModified = new GeneratedWhoModified(currentUserProvider);
     } else {
@@ -42,47 +42,47 @@ public class GeneratedPropertyFactory {
       generatedWhoModified = null;
     }
 
-		numberTypes.add(Integer.class.getName());
-		numberTypes.add(int.class.getName());
-		numberTypes.add(Long.class.getName());
-		numberTypes.add(long.class.getName());
-		numberTypes.add(Short.class.getName());
-		numberTypes.add(short.class.getName());
-		numberTypes.add(Double.class.getName());
-		numberTypes.add(double.class.getName());
-		numberTypes.add(BigDecimal.class.getName());
-	}
+    numberTypes.add(Integer.class.getName());
+    numberTypes.add(int.class.getName());
+    numberTypes.add(Long.class.getName());
+    numberTypes.add(long.class.getName());
+    numberTypes.add(Short.class.getName());
+    numberTypes.add(short.class.getName());
+    numberTypes.add(Double.class.getName());
+    numberTypes.add(double.class.getName());
+    numberTypes.add(BigDecimal.class.getName());
+  }
 
   public ClassLoadConfig getClassLoadConfig() {
     return classLoadConfig;
   }
 
   private boolean isNumberType(String typeClassName) {
-		return numberTypes.contains(typeClassName);
-	}
-	
-	public void setVersion(DeployBeanProperty property) {
-		if (isNumberType(property.getPropertyType().getName())) {
-			setCounter(property);
-		} else {
-			setUpdateTimestamp(property);
-		}
-	}
-	
-	public void setCounter(DeployBeanProperty property) {
-		
-		counterFactory.setCounter(property);
-	}
+    return numberTypes.contains(typeClassName);
+  }
 
-	public void setInsertTimestamp(DeployBeanProperty property) {
-		
-		insertFactory.setInsertTimestamp(property);
-	}
+  public void setVersion(DeployBeanProperty property) {
+    if (isNumberType(property.getPropertyType().getName())) {
+      setCounter(property);
+    } else {
+      setUpdateTimestamp(property);
+    }
+  }
 
-	public void setUpdateTimestamp(DeployBeanProperty property) {
-		
-		updateFactory.setUpdateTimestamp(property);
-	}
+  public void setCounter(DeployBeanProperty property) {
+
+    counterFactory.setCounter(property);
+  }
+
+  public void setInsertTimestamp(DeployBeanProperty property) {
+
+    insertFactory.setInsertTimestamp(property);
+  }
+
+  public void setUpdateTimestamp(DeployBeanProperty property) {
+
+    updateFactory.setUpdateTimestamp(property);
+  }
 
   public void setWhoCreated(DeployBeanProperty property) {
     if (generatedWhoCreated == null) {

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedUpdateDate.java

@@ -1,51 +1,51 @@
 package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
-import java.util.Date;
-
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
 
+import java.util.Date;
+
 /**
  * Generate a (java.util.Date) Timestamp whenever the bean is inserted or
  * updated.
  */
 public class GeneratedUpdateDate implements GeneratedProperty {
 
-    /**
-     * Return now as a Timestamp.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return new Date(System.currentTimeMillis());
-    }
+  /**
+   * Return now as a Timestamp.
+   */
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return new Date(now);
+  }
 
-    /**
-     * Return now as a Timestamp.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        return new Date(System.currentTimeMillis());
-    }
+  /**
+   * Return now as a Timestamp.
+   */
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    return new Date(now);
+  }
 
-    /**
-     * For dynamic table updates make sure this is included.
-     */
-    public boolean includeInUpdate() {
-        return true;
-    }
-    
-    @Override
-    public boolean includeInAllUpdates() {
-      return true;
-    }
+  /**
+   * For dynamic table updates make sure this is included.
+   */
+  public boolean includeInUpdate() {
+    return true;
+  }
 
-    /**
-     * Include this in every insert.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return true;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  /**
+   * Include this in every insert.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
+
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedUpdateJavaTime.java

@@ -3,10 +3,6 @@ package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
 
-import java.time.LocalDateTime;
-import java.time.OffsetDateTime;
-import java.time.ZonedDateTime;
-
 /**
  * Support java.time DateTime types as GeneratedProperty.
  */
@@ -41,13 +37,13 @@ public class GeneratedUpdateJavaTime {
   public static class LocalDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return LocalDateTime.now();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toLocalDateTime(now);
     }
 
     @Override
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-      return LocalDateTime.now();
+    public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toLocalDateTime(now);
     }
   }
 
@@ -57,13 +53,13 @@ public class GeneratedUpdateJavaTime {
   public static class OffsetDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return OffsetDateTime.now();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toOffsetDateTime(now);
     }
 
     @Override
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-      return OffsetDateTime.now();
+    public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toOffsetDateTime(now);
     }
   }
 
@@ -73,13 +69,13 @@ public class GeneratedUpdateJavaTime {
   public static class ZonedDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return ZonedDateTime.now();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toZonedDateTime(now);
     }
 
     @Override
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-      return ZonedDateTime.now();
+    public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+      return JavaTimeUtils.toZonedDateTime(now);
     }
   }
 

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedUpdateJodaTime.java

@@ -2,9 +2,8 @@ package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
-
-import org.joda.time.LocalDateTime;
 import org.joda.time.DateTime;
+import org.joda.time.LocalDateTime;
 
 /**
  * Support java.time DateTime types as GeneratedProperty.
@@ -40,13 +39,13 @@ public class GeneratedUpdateJodaTime {
   public static class LocalDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return new LocalDateTime();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return new LocalDateTime(now);
     }
 
     @Override
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-      return new LocalDateTime();
+    public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+      return new LocalDateTime(now);
     }
   }
 
@@ -56,13 +55,13 @@ public class GeneratedUpdateJodaTime {
   public static class DateTimeDT extends Base {
 
     @Override
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-      return new DateTime();
+    public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+      return new DateTime(now);
     }
 
     @Override
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-      return new DateTime();
+    public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+      return new DateTime(now);
     }
   }
 

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedUpdateLong.java

@@ -8,41 +8,41 @@ import com.avaje.ebeaninternal.server.deploy.BeanProperty;
  */
 public class GeneratedUpdateLong implements GeneratedProperty {
 
-    /**
-     * Return now as a Timestamp.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return System.currentTimeMillis();
-    }
+  /**
+   * Return now as a Timestamp.
+   */
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return now;
+  }
 
-    /**
-     * Return now as a Timestamp.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        return System.currentTimeMillis();
-    }
+  /**
+   * Return now as a Timestamp.
+   */
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    return now;
+  }
 
-    /**
-     * For dynamic table updates make sure this is included.
-     */
-    public boolean includeInUpdate() {
-        return true;
-    }
+  /**
+   * For dynamic table updates make sure this is included.
+   */
+  public boolean includeInUpdate() {
+    return true;
+  }
 
-    @Override
-    public boolean includeInAllUpdates() {
-      return true;
-    }
-    
-    /**
-     * Include this in every insert.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return true;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  /**
+   * Include this in every insert.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
+
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedUpdateTimestamp.java

@@ -1,50 +1,50 @@
 package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
-import java.sql.Timestamp;
-
 import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.server.deploy.BeanProperty;
 
+import java.sql.Timestamp;
+
 /**
  * Generate a Timestamp whenever the bean is inserted or updated.
  */
 public class GeneratedUpdateTimestamp implements GeneratedProperty, GeneratedWhenModified {
 
-    /**
-     * Return now as a Timestamp.
-     */
-    public Object getInsertValue(BeanProperty prop, EntityBean bean) {
-        return new Timestamp(System.currentTimeMillis());
-    }
+  /**
+   * Return now as a Timestamp.
+   */
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
+    return new Timestamp(now);
+  }
 
-    /**
-     * Return now as a Timestamp.
-     */
-    public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
-        return new Timestamp(System.currentTimeMillis());
-    }
+  /**
+   * Return now as a Timestamp.
+   */
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
+    return new Timestamp(now);
+  }
 
-    /**
-     * For dynamic table updates make sure this is included.
-     */
-    public boolean includeInUpdate() {
-        return true;
-    }
+  /**
+   * For dynamic table updates make sure this is included.
+   */
+  public boolean includeInUpdate() {
+    return true;
+  }
 
-    @Override
-    public boolean includeInAllUpdates() {
-      return true;
-    }
-    
-    /**
-     * Include this in every insert.
-     */
-    public boolean includeInInsert() {
-        return true;
-    }
+  @Override
+  public boolean includeInAllUpdates() {
+    return true;
+  }
 
-    public boolean isDDLNotNullable() {
-        return true;
-    }
+  /**
+   * Include this in every insert.
+   */
+  public boolean includeInInsert() {
+    return true;
+  }
+
+  public boolean isDDLNotNullable() {
+    return true;
+  }
 
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedWhoCreated.java

@@ -16,12 +16,12 @@ public class GeneratedWhoCreated implements GeneratedProperty {
   }
 
   @Override
-  public Object getInsertValue(BeanProperty prop, EntityBean bean) {
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
     return currentUserProvider.currentUser();
   }
 
   @Override
-  public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
     return null;
   }
 

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/GeneratedWhoModified.java

@@ -16,12 +16,12 @@ public class GeneratedWhoModified implements GeneratedProperty {
   }
 
   @Override
-  public Object getInsertValue(BeanProperty prop, EntityBean bean) {
+  public Object getInsertValue(BeanProperty prop, EntityBean bean, long now) {
     return currentUserProvider.currentUser();
   }
 
   @Override
-  public Object getUpdateValue(BeanProperty prop, EntityBean bean) {
+  public Object getUpdateValue(BeanProperty prop, EntityBean bean, long now) {
     return currentUserProvider.currentUser();
   }
 

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/InsertTimestampFactory.java

@@ -1,5 +1,9 @@
 package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
+import com.avaje.ebean.config.ClassLoadConfig;
+import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanProperty;
+
+import javax.persistence.PersistenceException;
 import java.sql.Timestamp;
 import java.time.LocalDateTime;
 import java.time.OffsetDateTime;
@@ -7,17 +11,12 @@ import java.time.ZonedDateTime;
 import java.util.HashMap;
 import java.util.Map;
 
-import javax.persistence.PersistenceException;
-
-import com.avaje.ebean.config.ClassLoadConfig;
-import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanProperty;
-
 /**
  * Helper for creating Insert timestamp GeneratedProperty objects.
  */
 public class InsertTimestampFactory {
 
-	final GeneratedInsertLong longTime = new GeneratedInsertLong();
+  final GeneratedInsertLong longTime = new GeneratedInsertLong();
 
   final Map<Class<?>, GeneratedProperty> map = new HashMap<Class<?>, GeneratedProperty>();
 
@@ -41,21 +40,21 @@ public class InsertTimestampFactory {
 
   public void setInsertTimestamp(DeployBeanProperty property) {
 
-		property.setGeneratedProperty(createInsertTimestamp(property));
-	}
-	
-	/**
-	 * Create the insert GeneratedProperty depending on the property type.
-	 */
-	public GeneratedProperty createInsertTimestamp(DeployBeanProperty property) {
-		
-		Class<?> propType = property.getPropertyType();
+    property.setGeneratedProperty(createInsertTimestamp(property));
+  }
+
+  /**
+   * Create the insert GeneratedProperty depending on the property type.
+   */
+  public GeneratedProperty createInsertTimestamp(DeployBeanProperty property) {
+
+    Class<?> propType = property.getPropertyType();
     GeneratedProperty generatedProperty = map.get(propType);
     if (generatedProperty != null) {
       return generatedProperty;
     }
 
-		throw new PersistenceException("Generated Insert Timestamp not supported on "+propType.getName());
-	}
-	
+    throw new PersistenceException("Generated Insert Timestamp not supported on " + propType.getName());
+  }
+
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/JavaTimeUtils.java

@@ -0,0 +1,34 @@
+package com.avaje.ebeaninternal.server.deploy.generatedproperty;
+
+import java.sql.Timestamp;
+import java.time.Instant;
+import java.time.OffsetDateTime;
+import java.time.ZoneId;
+import java.time.ZonedDateTime;
+
+/**
+ * Helper methods for Java time conversion.
+ */
+public class JavaTimeUtils {
+
+  /**
+   * Return the system millis time as a LocalDateTime.
+   */
+  public static Object toLocalDateTime(long systemMillis) {
+    return new Timestamp(systemMillis).toLocalDateTime();
+  }
+
+  /**
+   * Return the system millis time as a OffsetDateTime.
+   */
+  public static Object toOffsetDateTime(long systemMillis) {
+    return OffsetDateTime.ofInstant(Instant.ofEpochMilli(systemMillis), ZoneId.systemDefault());
+  }
+
+  /**
+   * Return the system millis time as a ZonedDateTime.
+   */
+  public static Object toZonedDateTime(long systemMillis) {
+    return ZonedDateTime.ofInstant(Instant.ofEpochMilli(systemMillis), ZoneId.systemDefault());
+  }
+}

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/UpdateTimestampFactory.java

@@ -1,5 +1,9 @@
 package com.avaje.ebeaninternal.server.deploy.generatedproperty;
 
+import com.avaje.ebean.config.ClassLoadConfig;
+import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanProperty;
+
+import javax.persistence.PersistenceException;
 import java.sql.Timestamp;
 import java.time.LocalDateTime;
 import java.time.OffsetDateTime;
@@ -7,17 +11,12 @@ import java.time.ZonedDateTime;
 import java.util.HashMap;
 import java.util.Map;
 
-import javax.persistence.PersistenceException;
-
-import com.avaje.ebean.config.ClassLoadConfig;
-import com.avaje.ebeaninternal.server.deploy.meta.DeployBeanProperty;
-
 /**
  * Helper for creating Update timestamp GeneratedProperty objects.
  */
 public class UpdateTimestampFactory {
 
-	final GeneratedUpdateLong longTime = new GeneratedUpdateLong();
+  final GeneratedUpdateLong longTime = new GeneratedUpdateLong();
 
   final Map<Class<?>, GeneratedProperty> map = new HashMap<Class<?>, GeneratedProperty>();
 
@@ -38,15 +37,15 @@ public class UpdateTimestampFactory {
     }
   }
 
-	public void setUpdateTimestamp(DeployBeanProperty property) {
+  public void setUpdateTimestamp(DeployBeanProperty property) {
 
-		property.setGeneratedProperty(createUpdateTimestamp(property));
-	}
-	
-	/**
-	 * Create the update GeneratedProperty depending on the property type.
-	 */
-	protected GeneratedProperty createUpdateTimestamp(DeployBeanProperty property) {
+    property.setGeneratedProperty(createUpdateTimestamp(property));
+  }
+
+  /**
+   * Create the update GeneratedProperty depending on the property type.
+   */
+  protected GeneratedProperty createUpdateTimestamp(DeployBeanProperty property) {
 
     Class<?> propType = property.getPropertyType();
     GeneratedProperty generatedProperty = map.get(propType);
@@ -54,7 +53,7 @@ public class UpdateTimestampFactory {
       return generatedProperty;
     }
 
-		throw new PersistenceException("Generated update Timestamp not supported on "+propType.getName());
-	}
-	
+    throw new PersistenceException("Generated update Timestamp not supported on " + propType.getName());
+  }
+
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/generatedproperty/package.html

@@ -1,7 +1,7 @@
 <HTML>
 <HEAD>
-	<META HTTP-EQUIV="CONTENT-TYPE" CONTENT="text/html; charset=iso-8859-1">
-	<TITLE>Counter, Insert Timestamp, Update Timestamp support</TITLE>
+  <META HTTP-EQUIV="CONTENT-TYPE" CONTENT="text/html; charset=iso-8859-1">
+  <TITLE>Counter, Insert Timestamp, Update Timestamp support</TITLE>
 </HEAD>
 <Body BGCOLOR="#ffffff">
 Counter, Insert Timestamp, Update Timestamp support

src/main/java/com/avaje/ebeaninternal/server/deploy/meta/DeployBeanDescriptor.java

@@ -33,7 +33,6 @@ import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 
 /**
  * Describes Beans including their deployment information.
@@ -763,7 +762,7 @@ public class DeployBeanDescriptor<T> {
   /**
    * Parse the include separating by comma or semicolon.
    */
-  public Set<String> parseDefaultSelectClause(String rawList) {
+  public LinkedHashSet<String> parseDefaultSelectClause(String rawList) {
 
     if (rawList == null) {
       return null;
@@ -780,7 +779,7 @@ public class DeployBeanDescriptor<T> {
         set.add(temp);
       }
     }
-    return Collections.unmodifiableSet(set);
+    return set;
   }
 
   /**

src/main/java/com/avaje/ebeaninternal/server/expression/AbstractExpression.java

@@ -1,5 +1,6 @@
 package com.avaje.ebeaninternal.server.expression;
 
+import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.ManyWhereJoins;
 import com.avaje.ebeaninternal.api.SpiExpression;
 import com.avaje.ebeaninternal.api.SpiExpressionRequest;
@@ -21,19 +22,20 @@ public abstract class AbstractExpression implements SpiExpression {
     this.propName = propName;
   }
 
-  public String getPropertyName() {
-    return propName;
+  @Override
+  public SpiExpression copyForPlanKey() {
+    return this;
   }
 
+  @Override
   public void containsMany(BeanDescriptor<?> desc, ManyWhereJoins manyWhereJoin) {
 
-    String propertyName = getPropertyName();
-    if (propertyName != null) {
-      ElPropertyDeploy elProp = desc.getElPropertyDeploy(propertyName);
+    if (propName != null) {
+      ElPropertyDeploy elProp = desc.getElPropertyDeploy(propName);
       if (elProp != null) {
         if (elProp.containsFormulaWithJoin()) {
           // for findRowCount query select clause
-          manyWhereJoin.addFormulaWithJoin(propertyName);
+          manyWhereJoin.addFormulaWithJoin(propName);
         }
         if (elProp.containsMany()) {
           // for findRowCount we join to a many property
@@ -44,13 +46,17 @@ public abstract class AbstractExpression implements SpiExpression {
   }
 
   @Override
-  public void validate(SpiExpressionValidation validation) {
-    validation.validate(getPropertyName());
+  public void prepareExpression(BeanQueryRequest<?> request) {
+    // do nothing
   }
 
-  protected ElPropertyValue getElProp(SpiExpressionRequest request) {
+  @Override
+  public void validate(SpiExpressionValidation validation) {
+    validation.validate(propName);
+  }
 
-    String propertyName = getPropertyName();
-    return request.getBeanDescriptor().getElGetValue(propertyName);
+  protected final ElPropertyValue getElProp(SpiExpressionRequest request) {
+
+    return request.getBeanDescriptor().getElGetValue(propName);
   }
 }

src/main/java/com/avaje/ebeaninternal/server/expression/AllEqualsExpression.java

@@ -1,9 +1,5 @@
 package com.avaje.ebeaninternal.server.expression;
 
-import java.util.Map;
-import java.util.Map.Entry;
-
-import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
 import com.avaje.ebeaninternal.api.ManyWhereJoins;
 import com.avaje.ebeaninternal.api.SpiExpression;
@@ -12,7 +8,11 @@ import com.avaje.ebeaninternal.api.SpiExpressionValidation;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
 import com.avaje.ebeaninternal.server.el.ElPropertyDeploy;
 
-class AllEqualsExpression implements SpiExpression {
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Map.Entry;
+
+class AllEqualsExpression extends NonPrepareExpression {
 
   private static final long serialVersionUID = -8691773558205937025L;
 
@@ -26,6 +26,7 @@ class AllEqualsExpression implements SpiExpression {
     return propName;
   }
 
+  @Override
   public void containsMany(BeanDescriptor<?> desc, ManyWhereJoins manyWhereJoin) {
     if (propMap != null) {
       for (String propertyName : propMap.keySet()) {
@@ -44,6 +45,7 @@ class AllEqualsExpression implements SpiExpression {
     }
   }
 
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
 
     if (propMap.isEmpty()) {
@@ -57,6 +59,7 @@ class AllEqualsExpression implements SpiExpression {
     }
   }
 
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
     if (propMap.isEmpty()) {
@@ -92,7 +95,8 @@ class AllEqualsExpression implements SpiExpression {
    * The null check is required due to the "is null" sql being generated.
    * </p>
    */
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
 
     builder.add(AllEqualsExpression.class);
 
@@ -100,14 +104,11 @@ class AllEqualsExpression implements SpiExpression {
       Object value = entry.getValue();
       String propName = entry.getKey();
       builder.add(propName).add(value == null ? 0 : 1);
-      builder.bind(value == null ? 0 : 1);
+      builder.bindIfNotNull(value);
     }
   }
 
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
-    queryAutoTuneHash(builder);
-  }
-
+  @Override
   public int queryBindHash() {
 
     int hc = 31;
@@ -117,4 +118,48 @@ class AllEqualsExpression implements SpiExpression {
 
     return hc;
   }
+
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof AllEqualsExpression)) {
+      return false;
+    }
+
+    AllEqualsExpression that = (AllEqualsExpression) other;
+    return isSameByValue(that, false);
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    if (!(other instanceof AllEqualsExpression)) {
+      return false;
+    }
+
+    AllEqualsExpression that = (AllEqualsExpression) other;
+    return isSameByValue(that, true);
+  }
+
+  private boolean isSameByValue(AllEqualsExpression that, boolean byValue) {
+
+    if (propMap.size() != that.propMap.size()) {
+      return false;
+    }
+
+    Iterator<Entry<String, Object>> thisIt = propMap.entrySet().iterator();
+    Iterator<Entry<String, Object>> thatIt = that.propMap.entrySet().iterator();
+
+    while (thisIt.hasNext() && thatIt.hasNext()) {
+      Entry<String, Object> thisNext = thisIt.next();
+      Entry<String, Object> thatNext = thatIt.next();
+
+      if (!thisNext.getKey().equals(thatNext.getKey())) {
+        return false;
+      }
+      if (!Same.sameBy(byValue, thisNext.getValue(), thatNext.getValue())) {
+        return false;
+      }
+    }
+
+    return true;
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/expression/BetweenExpression.java

@@ -1,10 +1,9 @@
 package com.avaje.ebeaninternal.server.expression;
 
-import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
+import com.avaje.ebeaninternal.api.SpiExpression;
 import com.avaje.ebeaninternal.api.SpiExpressionRequest;
 
-
 class BetweenExpression extends AbstractExpression {
 
   private static final long serialVersionUID = 2078918165221454910L;
@@ -21,28 +20,45 @@ class BetweenExpression extends AbstractExpression {
     this.valueHigh = valHigh;
   }
 
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
     request.addBindValue(valueLow);
     request.addBindValue(valueHigh);
   }
 
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
-    request.append(getPropertyName()).append(BETWEEN).append(" ? and ? ");
+    request.append(propName).append(BETWEEN).append(" ? and ? ");
   }
 
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
     builder.add(BetweenExpression.class).add(propName);
     builder.bind(2);
   }
 
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
-    queryAutoTuneHash(builder);
-  }
-
+  @Override
   public int queryBindHash() {
     int hc = valueLow.hashCode();
     hc = hc * 31 + valueHigh.hashCode();
     return hc;
   }
+
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof BetweenExpression)) {
+      return false;
+    }
+
+    BetweenExpression that = (BetweenExpression) other;
+    return this.propName.equals(that.propName);
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    BetweenExpression that = (BetweenExpression) other;
+    return valueLow.equals(that.valueLow)
+        && valueHigh.equals(that.valueHigh);
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/expression/BetweenPropertyExpression.java

@@ -1,6 +1,5 @@
 package com.avaje.ebeaninternal.server.expression;
 
-import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
 import com.avaje.ebeaninternal.api.ManyWhereJoins;
 import com.avaje.ebeaninternal.api.SpiExpression;
@@ -12,7 +11,7 @@ import com.avaje.ebeaninternal.server.el.ElPropertyDeploy;
 /**
  * Between expression where a value is between two properties.
  */
-class BetweenPropertyExpression implements SpiExpression {
+class BetweenPropertyExpression extends NonPrepareExpression {
 
   private static final long serialVersionUID = 2078918165221454910L;
 
@@ -32,6 +31,7 @@ class BetweenPropertyExpression implements SpiExpression {
     return propName;
   }
 
+  @Override
   public void containsMany(BeanDescriptor<?> desc, ManyWhereJoins manyWhereJoin) {
 
     ElPropertyDeploy elProp = desc.getElPropertyDeploy(name(lowProperty));
@@ -51,25 +51,42 @@ class BetweenPropertyExpression implements SpiExpression {
     validation.validate(highProperty);
   }
 
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
     request.addBindValue(value);
   }
 
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
     request.append(" ? ").append(BETWEEN).append(name(lowProperty)).append(" and ").append(name(highProperty));
   }
 
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
     builder.add(BetweenPropertyExpression.class).add(lowProperty).add(highProperty);
     builder.bind(1);
   }
 
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
-    queryAutoTuneHash(builder);
-  }
-
+  @Override
   public int queryBindHash() {
     return value.hashCode();
   }
+
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof BetweenPropertyExpression)) {
+      return false;
+    }
+
+    BetweenPropertyExpression that = (BetweenPropertyExpression) other;
+    return lowProperty.equals(that.lowProperty)
+        && highProperty.equals(that.highProperty);
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    BetweenPropertyExpression that = (BetweenPropertyExpression) other;
+    return value.equals(that.value);
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/expression/CaseInsensitiveEqualExpression.java

@@ -1,7 +1,7 @@
 package com.avaje.ebeaninternal.server.expression;
 
-import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
+import com.avaje.ebeaninternal.api.SpiExpression;
 import com.avaje.ebeaninternal.api.SpiExpressionRequest;
 import com.avaje.ebeaninternal.server.el.ElPropertyValue;
 
@@ -16,6 +16,7 @@ class CaseInsensitiveEqualExpression extends AbstractExpression {
     this.value = value.toLowerCase();
   }
 
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
 
     ElPropertyValue prop = getElProp(request);
@@ -28,29 +29,42 @@ class CaseInsensitiveEqualExpression extends AbstractExpression {
     request.addBindValue(value);
   }
 
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
-    String propertyName = getPropertyName();
-    String pname = propertyName;
-
+    String pname = propName;
     ElPropertyValue prop = getElProp(request);
     if (prop != null && prop.isDbEncrypted()) {
-      pname = prop.getBeanProperty().getDecryptProperty(propertyName);
+      pname = prop.getBeanProperty().getDecryptProperty(propName);
     }
 
     request.append("lower(").append(pname).append(") =? ");
   }
 
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
     builder.add(CaseInsensitiveEqualExpression.class).add(propName);
     builder.bind(1);
   }
 
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
-    queryAutoTuneHash(builder);
-  }
-
+  @Override
   public int queryBindHash() {
     return value.hashCode();
   }
+
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof CaseInsensitiveEqualExpression)) {
+      return false;
+    }
+
+    CaseInsensitiveEqualExpression that = (CaseInsensitiveEqualExpression) other;
+    return this.propName.equals(that.propName);
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    CaseInsensitiveEqualExpression that = (CaseInsensitiveEqualExpression) other;
+    return value.equals(that.value);
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExampleExpression.java

@@ -86,6 +86,20 @@ public class DefaultExampleExpression implements SpiExpression, ExampleExpressio
     this.likeType = likeType;
   }
 
+  DefaultExampleExpression(ArrayList<SpiExpression> source) {
+    this.entity = null;
+    this.list = new ArrayList<SpiExpression>(source.size());
+    for (SpiExpression expression : source) {
+      list.add(expression.copyForPlanKey());
+    }
+  }
+
+  @Override
+  public SpiExpression copyForPlanKey() {
+    return new DefaultExampleExpression(list);
+  }
+
+  @Override
   public void containsMany(BeanDescriptor<?> desc, ManyWhereJoins whereManyJoins) {
     if (list != null) {
       for (int i = 0; i < list.size(); i++) {
@@ -94,31 +108,37 @@ public class DefaultExampleExpression implements SpiExpression, ExampleExpressio
     }
   }
 
+  @Override
   public ExampleExpression includeZeros() {
     includeZeros = true;
     return this;
   }
 
+  @Override
   public ExampleExpression caseInsensitive() {
     caseInsensitive = true;
     return this;
   }
 
+  @Override
   public ExampleExpression useStartsWith() {
     likeType = LikeType.STARTS_WITH;
     return this;
   }
 
+  @Override
   public ExampleExpression useContains() {
     likeType = LikeType.CONTAINS;
     return this;
   }
 
+  @Override
   public ExampleExpression useEndsWith() {
     likeType = LikeType.ENDS_WITH;
     return this;
   }
 
+  @Override
   public ExampleExpression useEqualTo() {
     likeType = LikeType.EQUAL_TO;
     return this;
@@ -134,6 +154,7 @@ public class DefaultExampleExpression implements SpiExpression, ExampleExpressio
   /**
    * Adds bind values to the request.
    */
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
 
     for (int i = 0; i < list.size(); i++) {
@@ -145,6 +166,7 @@ public class DefaultExampleExpression implements SpiExpression, ExampleExpressio
   /**
    * Generates and adds the sql to the request.
    */
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
     if (!list.isEmpty()) {
@@ -162,34 +184,27 @@ public class DefaultExampleExpression implements SpiExpression, ExampleExpressio
     }
   }
 
-  /**
-   * Return a hash for AutoTune query identification.
-   */
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
-    // we have not yet built the list of expressions
-    // so just based on the class name
-    builder.add(DefaultExampleExpression.class);
+  @Override
+  public void prepareExpression(BeanQueryRequest<?> request) {
+    list = buildExpressions(request);
   }
 
   /**
-   * Return a hash for query plan identification.
+   * Return a hash for AutoTune query identification.
    */
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
-
-    // this is always called once, and always called before
-    // addSql() and addBindValues() methods
-    list = buildExpressions(request);
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
 
     builder.add(DefaultExampleExpression.class);
-
     for (int i = 0; i < list.size(); i++) {
-      list.get(i).queryPlanHash(request, builder);
+      list.get(i).queryPlanHash(builder);
     }
   }
 
   /**
    * Return a hash for the actual bind values used.
    */
+  @Override
   public int queryBindHash() {
     int hc = DefaultExampleExpression.class.getName().hashCode();
     for (int i = 0; i < list.size(); i++) {
@@ -199,6 +214,38 @@ public class DefaultExampleExpression implements SpiExpression, ExampleExpressio
     return hc;
   }
 
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof DefaultExampleExpression)) {
+      return false;
+    }
+
+    DefaultExampleExpression that = (DefaultExampleExpression) other;
+    if (this.list.size() != that.list.size()) {
+      return false;
+    }
+    for (int i = 0; i < list.size(); i++) {
+      if (!list.get(i).isSameByPlan(that.list.get(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    DefaultExampleExpression that = (DefaultExampleExpression) other;
+    if (this.list.size() != that.list.size()) {
+      return false;
+    }
+    for (int i = 0; i < list.size(); i++) {
+      if (!list.get(i).isSameByBind(that.list.get(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
+
   /**
    * Build the List of expressions.
    */

src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExpressionList.java

@@ -1,4 +1,4 @@
-package com.avaje.ebeaninternal.util;
+package com.avaje.ebeaninternal.server.expression;
 
 import java.sql.Timestamp;
 import java.util.ArrayList;
@@ -56,6 +56,10 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
     this.listAndJoin = " and ";
   }
 
+  private DefaultExpressionList() {
+    this(null, null, null, new ArrayList<SpiExpression>());
+  }
+
   @Override
   public SpiExpressionList<?> trimPath(int prefixTrim) {
     throw new RuntimeException("Only allowed on FilterExpressionList");
@@ -65,17 +69,6 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
     return list;
   }
 
-  /**
-   * Set the ExpressionFactory.
-   * <p>
-   * After deserialisation so that it can be further modified.
-   * </p>
-   */
-  @Override
-  public void setExpressionFactory(ExpressionFactory expr) {
-    this.expr = expr;
-  }
-
   /**
    * Return a copy of the expression list.
    * <p>
@@ -88,6 +81,14 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
     return copy;
   }
 
+  public DefaultExpressionList<T> copyForPlanKey() {
+    DefaultExpressionList<T> copy = new DefaultExpressionList<T>();
+    for (int i = 0; i < list.size(); i++) {
+      copy.list.add(list.get(i).copyForPlanKey());
+    }
+    return copy;
+  }
+
   /**
    * Return true if one of the expressions is related to a Many property.
    */
@@ -325,7 +326,7 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
   }
 
   @Override
-  public String buildSql(SpiExpressionRequest request) {
+  public void addSql(SpiExpressionRequest request) {
 
     request.append(listAndStart);
     for (int i = 0, size = list.size(); i < size; i++) {
@@ -336,28 +337,19 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
       expression.addSql(request);
     }
     request.append(listAndEnd);
-    return request.getSql();
   }
 
   @Override
-  public ArrayList<Object> buildBindValues(SpiExpressionRequest request) {
-
+  public void addBindValues(SpiExpressionRequest request) {
     for (int i = 0, size = list.size(); i < size; i++) {
-      SpiExpression expression = list.get(i);
-      expression.addBindValues(request);
+      list.get(i).addBindValues(request);
     }
-    return request.getBindValues();
   }
 
-  /**
-   * Calculate a hash based on the expressions but excluding the actual bind
-   * values.
-   */
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
-    builder.add(DefaultExpressionList.class);
+  @Override
+  public void prepareExpression(BeanQueryRequest<?> request) {
     for (int i = 0, size = list.size(); i < size; i++) {
-      SpiExpression expression = list.get(i);
-      expression.queryAutoTuneHash(builder);
+      list.get(i).prepareExpression(request);
     }
   }
 
@@ -366,26 +358,57 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
    * values.
    */
   @Override
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
     builder.add(DefaultExpressionList.class);
     for (int i = 0, size = list.size(); i < size; i++) {
-      SpiExpression expression = list.get(i);
-      expression.queryPlanHash(request, builder);
+      list.get(i).queryPlanHash(builder);
     }
   }
 
   /**
    * Calculate a hash based on the expressions.
    */
+  @Override
   public int queryBindHash() {
     int hash = DefaultExpressionList.class.getName().hashCode();
     for (int i = 0, size = list.size(); i < size; i++) {
-      SpiExpression expression = list.get(i);
-      hash = hash * 31 + expression.queryBindHash();
+      hash = hash * 31 + list.get(i).queryBindHash();
     }
     return hash;
   }
 
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof DefaultExpressionList)) {
+      return false;
+    }
+
+    DefaultExpressionList<?> that = (DefaultExpressionList<?>)other;
+    if (list.size() != that.list.size()) {
+      return false;
+    }
+    for (int i = 0, size = list.size(); i < size; i++) {
+      if (!list.get(i).isSameByPlan(that.list.get(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    DefaultExpressionList<?> that = (DefaultExpressionList<?>)other;
+    if (list.size() != that.list.size()) {
+      return false;
+    }
+    for (int i = 0, size = list.size(); i < size; i++) {
+      if (!list.get(i).isSameByBind(that.list.get(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
+
   /**
    * Path exists - for the given path in a JSON document.
    */

src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExpressionRequest.java

@@ -1,7 +1,8 @@
-package com.avaje.ebeaninternal.util;
+package com.avaje.ebeaninternal.server.expression;
 
 import java.sql.SQLException;
 import java.util.ArrayList;
+import java.util.List;
 
 import com.avaje.ebeaninternal.api.SpiExpressionList;
 import com.avaje.ebeaninternal.api.SpiExpressionRequest;
@@ -20,7 +21,7 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
 
   private final StringBuilder sql = new StringBuilder();
 
-  private final ArrayList<Object> bindValues = new ArrayList<Object>();
+  private final List<Object> bindValues = new ArrayList<Object>();
 
   private final DeployParser deployParser;
 
@@ -39,7 +40,7 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
     this.binder = binder;
     this.expressionList = expressionList;
     // immediately build the list of bind values (callback style)
-    expressionList.buildBindValues(this);
+    expressionList.addBindValues(this);
   }
 
   public DefaultExpressionRequest(BeanDescriptor<?> beanDescriptor) {
@@ -54,7 +55,8 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
    * Build sql for the underlying expression list.
    */
   public String buildSql() {
-    return expressionList.buildSql(this);
+    expressionList.addSql(this);
+    return sql.toString();
   }
 
   /**
@@ -70,10 +72,12 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
     }
   }
 
+  @Override
   public JsonExpressionHandler getJsonHandler() {
     return binder.getJsonExpressionHandler();
   }
 
+  @Override
   public String parseDeploy(String logicalProp) {
 
     String s = deployParser.getDeployWord(logicalProp);
@@ -93,14 +97,17 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
   /**
    * Increments the parameter index and returns that value.
    */
+  @Override
   public int nextParameter() {
     return ++paramIndex;
   }
 
+  @Override
   public BeanDescriptor<?> getBeanDescriptor() {
     return beanDescriptor;
   }
 
+  @Override
   public SpiOrmQueryRequest<?> getQueryRequest() {
     return queryRequest;
   }
@@ -108,16 +115,19 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
   /**
    * Append text the underlying sql expression.
    */
+  @Override
   public SpiExpressionRequest append(String sqlExpression) {
     sql.append(sqlExpression);
     return this;
   }
 
+  @Override
   public void addBindEncryptKey(Object bindValue) {
     bindValues.add(bindValue);
     bindLog("****");
   }
 
+  @Override
   public void addBindValue(Object bindValue) {
     bindValues.add(bindValue);
     bindLog(bindValue);
@@ -136,11 +146,13 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
     return bindLog == null ? "" : bindLog.toString();
   }
 
+  @Override
   public String getSql() {
     return sql.toString();
   }
 
-  public ArrayList<Object> getBindValues() {
+  @Override
+  public List<Object> getBindValues() {
     return bindValues;
   }
 

src/main/java/com/avaje/ebeaninternal/server/expression/ExistsExpression.java

@@ -17,71 +17,103 @@ public class ExistsExpression implements SpiExpression {
 
   private static final long serialVersionUID = 666990277309851644L;
 
-  private final boolean not;
+  protected final boolean not;
 
-  private final SpiQuery<?> subQuery;
+  protected final SpiQuery<?> subQuery;
 
-  private transient CQuery<?> compiledSubQuery;
+  protected List<Object> bindParams;
+
+  protected String sql;
 
   public ExistsExpression(SpiQuery<?> subQuery, boolean not) {
     this.subQuery = subQuery;
     this.not = not;
   }
 
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
-    builder.add(ExistsExpression.class).add(not);
-
-    subQuery.queryAutoTuneHash(builder);
+  ExistsExpression(boolean not, String sql , List<Object> bindParams) {
+    this.not = not;
+    this.sql = sql;
+    this.bindParams = bindParams;
+    this.subQuery = null;
   }
 
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
+  @Override
+  public void prepareExpression(BeanQueryRequest<?> request) {
 
-    // queryPlanHash executes prior to addSql() or addBindValues()
-    // ... so compiledQuery will exist
-    compiledSubQuery = compileSubQuery(request);
+    CQuery<?> subQuery = compileSubQuery(request);
+    this.bindParams = subQuery.getPredicates().getWhereExprBindValues();
+    this.sql = subQuery.getGeneratedSql().replace('\n', ' ');
+  }
 
-    queryAutoTuneHash(builder);
+  @Override
+  public SpiExpression copyForPlanKey() {
+    return this;
   }
 
   /**
    * Compile/build the sub query.
    */
-  private CQuery<?> compileSubQuery(BeanQueryRequest<?> queryRequest) {
-
+  protected CQuery<?> compileSubQuery(BeanQueryRequest<?> queryRequest) {
     SpiEbeanServer ebeanServer = (SpiEbeanServer) queryRequest.getEbeanServer();
     return ebeanServer.compileQuery(subQuery, queryRequest.getTransaction());
   }
 
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
+    builder.add(ExistsExpression.class).add(not);
+    builder.add(sql).add(bindParams.size());
+  }
+
+  @Override
   public int queryBindHash() {
     return subQuery.queryBindHash();
   }
 
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
-    String subSelect = compiledSubQuery.getGeneratedSql();
-    subSelect = subSelect.replace('\n', ' ');
-
     if (not) {
       request.append(" not");
     }
     request.append(" exists (");
-    request.append(subSelect);
+    request.append(sql);
     request.append(") ");
   }
 
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
 
-    List<Object> bindParams = compiledSubQuery.getPredicates().getWhereExprBindValues();
-
-    if (bindParams == null) {
-      return;
-    }
-
     for (int i = 0; i < bindParams.size(); i++) {
       request.addBindValue(bindParams.get(i));
     }
   }
 
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof ExistsExpression)) {
+      return false;
+    }
+
+    ExistsExpression that = (ExistsExpression) other;
+    return this.sql.equals(that.sql)
+        && this.not == that.not
+        && this.bindParams.size() == that.bindParams.size();
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    ExistsExpression that = (ExistsExpression) other;
+    if (this.bindParams.size() != that.bindParams.size()) {
+      return false;
+    }
+    for (int i = 0; i < bindParams.size(); i++) {
+      if (!bindParams.get(i).equals(that.bindParams.get(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
+
   @Override
   public void containsMany(BeanDescriptor<?> desc, ManyWhereJoins whereManyJoins) {
     // Nothing to do for exists expression

src/main/java/com/avaje/ebeaninternal/server/expression/FilterExpressionList.java

@@ -1,8 +1,7 @@
-package com.avaje.ebeaninternal.util;
+package com.avaje.ebeaninternal.server.expression;
 
 import com.avaje.ebean.*;
 import com.avaje.ebeaninternal.api.SpiExpressionList;
-import com.avaje.ebeaninternal.server.expression.FilterExprPath;
 
 import javax.persistence.PersistenceException;
 import java.util.List;

src/main/java/com/avaje/ebeaninternal/server/expression/IdExpression.java

@@ -1,18 +1,16 @@
 package com.avaje.ebeaninternal.server.expression;
 
-import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
 import com.avaje.ebeaninternal.api.ManyWhereJoins;
 import com.avaje.ebeaninternal.api.SpiExpression;
 import com.avaje.ebeaninternal.api.SpiExpressionRequest;
 import com.avaje.ebeaninternal.api.SpiExpressionValidation;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
-import com.avaje.ebeaninternal.util.DefaultExpressionRequest;
 
 /**
  * Slightly redundant as Query.setId() ultimately also does the same job.
  */
-class IdExpression implements SpiExpression {
+class IdExpression extends NonPrepareExpression implements SpiExpression {
 
   private static final long serialVersionUID = -3065936341718489842L;
 
@@ -25,6 +23,7 @@ class IdExpression implements SpiExpression {
   /**
    * Always returns false.
    */
+  @Override
   public void containsMany(BeanDescriptor<?> desc, ManyWhereJoins manyWhereJoin) {
 
   }
@@ -34,6 +33,7 @@ class IdExpression implements SpiExpression {
     // always valid
   }
 
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
 
     // 'flatten' EmbeddedId and multiple Id cases
@@ -45,6 +45,7 @@ class IdExpression implements SpiExpression {
     }
   }
 
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
     DefaultExpressionRequest r = (DefaultExpressionRequest) request;
@@ -56,17 +57,25 @@ class IdExpression implements SpiExpression {
   /**
    * No properties so this is just a unique static number.
    */
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
     builder.add(IdExpression.class);
     builder.bind(1);
   }
 
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
-    queryAutoTuneHash(builder);
-  }
-
+  @Override
   public int queryBindHash() {
     return value.hashCode();
   }
 
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    return other instanceof IdExpression;
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    IdExpression that = (IdExpression) other;
+    return value.equals(that.value);
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/expression/IdInExpression.java

@@ -1,8 +1,5 @@
 package com.avaje.ebeaninternal.server.expression;
 
-import java.util.List;
-
-import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
 import com.avaje.ebeaninternal.api.ManyWhereJoins;
 import com.avaje.ebeaninternal.api.SpiExpression;
@@ -10,12 +7,13 @@ import com.avaje.ebeaninternal.api.SpiExpressionRequest;
 import com.avaje.ebeaninternal.api.SpiExpressionValidation;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
 import com.avaje.ebeaninternal.server.deploy.id.IdBinder;
-import com.avaje.ebeaninternal.util.DefaultExpressionRequest;
+
+import java.util.List;
 
 /**
  * Slightly redundant as Query.setId() ultimately also does the same job.
  */
-public class IdInExpression implements SpiExpression {
+public class IdInExpression extends NonPrepareExpression {
 
   private static final long serialVersionUID = 1L;
 
@@ -25,6 +23,7 @@ public class IdInExpression implements SpiExpression {
     this.idList = idList;
   }
 
+  @Override
   public void containsMany(BeanDescriptor<?> desc, ManyWhereJoins manyWhereJoin) {
   }
 
@@ -33,6 +32,7 @@ public class IdInExpression implements SpiExpression {
     // always valid
   }
 
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
 
     // Bind the Id values including EmbeddedId and multiple Id
@@ -60,6 +60,7 @@ public class IdInExpression implements SpiExpression {
     request.append(inClause);
   }
 
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
     DefaultExpressionRequest r = (DefaultExpressionRequest) request;
@@ -74,17 +75,38 @@ public class IdInExpression implements SpiExpression {
   /**
    * Incorporates the number of Id values to bind.
    */
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
     builder.add(IdInExpression.class).add(idList.size());
     builder.bind(idList.size());
   }
 
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
-    queryAutoTuneHash(builder);
-  }
-
+  @Override
   public int queryBindHash() {
     return idList.hashCode();
   }
 
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof IdInExpression)) {
+      return false;
+    }
+
+    IdInExpression that = (IdInExpression) other;
+    return this.idList.size() == that.idList.size();
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    IdInExpression that = (IdInExpression) other;
+    if (this.idList.size() != that.idList.size()) {
+      return false;
+    }
+    for (int i = 0; i < idList.size(); i++) {
+      if (!idList.get(i).equals(that.idList.get(i))) {
+        return false;
+      }
+    }
+    return true;
+  }
 }

src/main/java/com/avaje/ebeaninternal/server/expression/InExpression.java

@@ -1,8 +1,8 @@
 package com.avaje.ebeaninternal.server.expression;
 
 import com.avaje.ebean.bean.EntityBean;
-import com.avaje.ebean.event.BeanQueryRequest;
 import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
+import com.avaje.ebeaninternal.api.SpiExpression;
 import com.avaje.ebeaninternal.api.SpiExpressionRequest;
 import com.avaje.ebeaninternal.server.el.ElPropertyValue;
 
@@ -28,6 +28,7 @@ class InExpression extends AbstractExpression {
     this.not = not;
   }
 
+  @Override
   public void addBindValues(SpiExpressionRequest request) {
 
     ElPropertyValue prop = getElProp(request);
@@ -51,6 +52,7 @@ class InExpression extends AbstractExpression {
     }
   }
 
+  @Override
   public void addSql(SpiExpressionRequest request) {
 
     if (values.length == 0) {
@@ -59,20 +61,18 @@ class InExpression extends AbstractExpression {
       return;
     }
 
-    String propertyName = getPropertyName();
-
     ElPropertyValue prop = getElProp(request);
     if (prop != null && !prop.isAssocId()) {
       prop = null;
     }
 
     if (prop != null) {
-      request.append(prop.getAssocIdInExpr(propertyName));
+      request.append(prop.getAssocIdInExpr(propName));
       String inClause = prop.getAssocIdInValueExpr(values.length);
       request.append(inClause);
 
     } else {
-      request.append(propertyName);
+      request.append(propName);
       if (not) {
         request.append(" not");
       }
@@ -88,15 +88,13 @@ class InExpression extends AbstractExpression {
   /**
    * Based on the number of values in the in clause.
    */
-  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
+  @Override
+  public void queryPlanHash(HashQueryPlanBuilder builder) {
     builder.add(InExpression.class).add(propName).add(values.length).add(not);
     builder.bind(values.length);
   }
 
-  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
-    queryAutoTuneHash(builder);
-  }
-
+  @Override
   public int queryBindHash() {
     int hc = 31;
     for (int i = 0; i < values.length; i++) {
@@ -105,4 +103,29 @@ class InExpression extends AbstractExpression {
     return hc;
   }
 
+  @Override
+  public boolean isSameByPlan(SpiExpression other) {
+    if (!(other instanceof InExpression)) {
+      return false;
+    }
+
+    InExpression that = (InExpression) other;
+    return propName.equals(that.propName)
+        && not == that.not
+        && values.length == that.values.length;
+  }
+
+  @Override
+  public boolean isSameByBind(SpiExpression other) {
+    InExpression that = (InExpression) other;
+    if (this.values.length != that.values.length) {
+      return false;
+    }
+    for (int i = 0; i < values.length; i++) {
+      if (!values[i].equals(that.values[i])) {
+        return false;
+      }
+    }
+    return true;
+  }
 }