ENH: Support @Index platforms attribute - platform specific indexes

This is a potential alternative to using extra-dll.xml. Might be
appropriate to use over extra-dll in small simple cases.

We might look to extend this in the future to allow full raw platform specific ddl - the ability to specify the entire create index statement.

src/main/java/io/ebean/config/DbConstraintNormalise.java

@@ -41,17 +41,20 @@ public class DbConstraintNormalise {
   }
 
   /**
-   * Normalise the column name by removing any quoted identifier characters.
+   * Normalise the column name by removing any quoted identifier characters and formula brackets.
    */
   public String normaliseColumn(String columnName) {
-
-    columnName = trimQuotes(columnName);
+    columnName = trimBrackets(trimQuotes(columnName));
     if (lowerCaseColumns) {
       columnName = columnName.toLowerCase();
     }
     return columnName;
   }
 
+  private String trimBrackets(String value) {
+    return value.replace("(","").replace(")","");
+  }
+
   /**
    * Lower case the table name checking for quoted identifiers.
    */

src/main/java/io/ebeaninternal/dbmigration/ddlgeneration/platform/BaseTableDdl.java

@@ -112,8 +112,8 @@ public class BaseTableDdl implements TableDdl {
         handleStrictError(tableName, columnName);
       }
 
-      before = getScriptsForPlatform(column.getBefore(), platformDdl.getPlatform().getName());
-      after = getScriptsForPlatform(column.getAfter(), platformDdl.getPlatform().getName());
+      before = getScriptsForPlatform(column.getBefore());
+      after = getScriptsForPlatform(column.getAfter());
       this.withHistory = withHistory;
     }
 
@@ -136,9 +136,9 @@ public class BaseTableDdl implements TableDdl {
         }
         before = Collections.singletonList(platformDdl.getUpdateNullWithDefault());
       } else {
-        before = getScriptsForPlatform(alter.getBefore(), platformDdl.getPlatform().getName());
+        before = getScriptsForPlatform(alter.getBefore());
       }
-      after = getScriptsForPlatform(alter.getAfter(), platformDdl.getPlatform().getName());
+      after = getScriptsForPlatform(alter.getAfter());
     }
 
     void writeBefore(DdlBuffer buffer) throws IOException {
@@ -167,7 +167,8 @@ public class BaseTableDdl implements TableDdl {
       }
     }
 
-    private List<String> getScriptsForPlatform(List<DdlScript> scripts, String searchPlatform) {
+    private List<String> getScriptsForPlatform(List<DdlScript> scripts) {
+      String searchPlatform = platformDdl.getPlatform().getName();
       List<String> ret = Collections.emptyList();
       for (DdlScript script : scripts) {
         if (script.getPlatforms() == null || script.getPlatforms().isEmpty()) {
@@ -358,7 +359,6 @@ public class BaseTableDdl implements TableDdl {
    * For all other DB platforms these unique constraints are done inline as per normal.
    */
   protected void writeUniqueOneToOneConstraints(DdlWrite write, CreateTable createTable) throws IOException {
-
     String tableName = createTable.getName();
     for (Column col : externalUnique) {
       String uqName = col.getUniqueOneToOne();
@@ -381,7 +381,6 @@ public class BaseTableDdl implements TableDdl {
   }
 
   protected void writeSequence(DdlWrite writer, CreateTable createTable, String pk) throws IOException {
-
     // explicit sequence use or platform decides
     String explicitSequenceName = createTable.getSequenceName();
     int initial = toInt(createTable.getSequenceInitial());
@@ -400,13 +399,11 @@ public class BaseTableDdl implements TableDdl {
   }
 
   protected void createWithHistory(DdlWrite writer, String name) throws IOException {
-
     MTable table = writer.getTable(name);
     platformDdl.createWithHistory(writer, table);
   }
 
   protected void writeInlineForeignKeys(DdlWrite write, CreateTable createTable) throws IOException {
-
     for (Column column : createTable.getColumn()) {
       String references = column.getReferences();
       if (hasValue(references)) {
@@ -417,13 +414,11 @@ public class BaseTableDdl implements TableDdl {
   }
 
   protected void writeInlineForeignKey(DdlWrite write, Column column) throws IOException {
-
     String fkConstraint = platformDdl.tableInlineForeignKey(new WriteForeignKey(null, column));
     write.apply().append(",").newLine().append("  ").append(fkConstraint);
   }
 
   protected void writeInlineCompoundForeignKeys(DdlWrite write, CreateTable createTable) throws IOException {
-
     for (ForeignKey key : createTable.getForeignKey()) {
       String fkConstraint = platformDdl.tableInlineForeignKey(new WriteForeignKey(null, key));
       write.apply().append(",").newLine().append("  ").append(fkConstraint);
@@ -431,7 +426,6 @@ public class BaseTableDdl implements TableDdl {
   }
 
   protected void writeAddForeignKeys(DdlWrite write, CreateTable createTable) throws IOException {
-
     for (Column column : createTable.getColumn()) {
       String references = column.getReferences();
       if (hasValue(references)) {
@@ -443,7 +437,6 @@ public class BaseTableDdl implements TableDdl {
   }
 
   protected void writeAddCompoundForeignKeys(DdlWrite write, CreateTable createTable) throws IOException {
-
     for (ForeignKey key : createTable.getForeignKey()) {
       writeForeignKey(write, new WriteForeignKey(createTable.getName(), key));
     }
@@ -454,7 +447,6 @@ public class BaseTableDdl implements TableDdl {
   }
 
   protected void writeForeignKey(DdlWrite write, WriteForeignKey request) throws IOException {
-
     DdlBuffer fkeyBuffer = write.applyForeignKeys();
     String tableName = lowerTableName(request.table());
     if (request.indexName() != null) {
@@ -474,7 +466,6 @@ public class BaseTableDdl implements TableDdl {
   }
 
   protected void alterTableAddForeignKey(DdlOptions options, DdlBuffer buffer, WriteForeignKey request) throws IOException {
-
     buffer.appendStatement(platformDdl.alterTableAddForeignKey(options, request));
   }
 
@@ -493,7 +484,6 @@ public class BaseTableDdl implements TableDdl {
    * Add 'drop table' statement to the buffer.
    */
   protected void dropTable(DdlBuffer buffer, String tableName) throws IOException {
-
     buffer.appendStatement(platformDdl.dropTable(tableName));
   }
 
@@ -501,26 +491,38 @@ public class BaseTableDdl implements TableDdl {
    * Add 'drop sequence' statement to the buffer.
    */
   protected void dropSequence(DdlBuffer buffer, String sequenceName) throws IOException {
-
     buffer.appendStatement(platformDdl.dropSequence(sequenceName));
   }
 
   protected void writeCompoundUniqueConstraints(DdlBuffer apply, CreateTable createTable) throws IOException {
-
     boolean inlineUniqueWhenNull = platformDdl.isInlineUniqueWhenNullable();
     for (UniqueConstraint uniqueConstraint : createTable.getUniqueConstraint()) {
-       if (inlineUniqueWhenNull) {
-        String uqName = uniqueConstraint.getName();
-        String[] columns = split(uniqueConstraint.getColumnNames());
-        apply.append(",").newLine();
-        apply.append("  constraint ").append(uqName).append(" unique");
-        appendColumns(columns, apply);
-      } else {
-        externalCompoundUnique.add(uniqueConstraint);
+      if (platformInclude(uniqueConstraint.getPlatforms())) {
+        if (inlineUniqueWhenNull) {
+          String uqName = uniqueConstraint.getName();
+          apply.append(",").newLine();
+          apply.append("  constraint ").append(uqName).append(" unique");
+          appendColumns(split(uniqueConstraint.getColumnNames()), apply);
+        } else {
+          externalCompoundUnique.add(uniqueConstraint);
+        }
       }
     }
   }
 
+  private boolean platformInclude(String platforms) {
+    if (platforms == null || platforms.isEmpty()) {
+      return true;
+    }
+    String currentPlatform = platformDdl.getPlatform().getPlatform().name();
+    for (String name : StringHelper.splitNames(platforms)) {
+      if (currentPlatform.equalsIgnoreCase(name)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
   /**
    * Write the unique constraints inline with the create table statement.
    */
@@ -608,25 +610,30 @@ public class BaseTableDdl implements TableDdl {
 
   @Override
   public void generate(DdlWrite writer, CreateIndex createIndex) throws IOException {
-    writer.apply().appendStatement(platformDdl.createIndex(createIndex.getIndexName(), createIndex.getTableName(), split(createIndex.getColumns())));
-    writer.dropAll().appendStatement(platformDdl.dropIndex(createIndex.getIndexName(), createIndex.getTableName()));
+    if (platformInclude(createIndex.getPlatforms())) {
+      writer.apply().appendStatement(platformDdl.createIndex(createIndex.getIndexName(), createIndex.getTableName(), split(createIndex.getColumns())));
+      writer.dropAll().appendStatement(platformDdl.dropIndex(createIndex.getIndexName(), createIndex.getTableName()));
+    }
   }
 
   @Override
   public void generate(DdlWrite writer, DropIndex dropIndex) throws IOException {
-    writer.apply().appendStatement(platformDdl.dropIndex(dropIndex.getIndexName(), dropIndex.getTableName()));
+    if (platformInclude(dropIndex.getPlatforms())) {
+      writer.apply().appendStatement(platformDdl.dropIndex(dropIndex.getIndexName(), dropIndex.getTableName()));
+    }
   }
 
   @Override
   public void generate(DdlWrite writer, AddUniqueConstraint constraint) throws IOException {
+    if (platformInclude(constraint.getPlatforms())) {
+      if (DdlHelp.isDropConstraint(constraint.getColumnNames())) {
+        writer.apply().appendStatement(platformDdl.alterTableDropUniqueConstraint(constraint.getTableName(), constraint.getConstraintName()));
 
-    if (DdlHelp.isDropConstraint(constraint.getColumnNames())) {
-      writer.apply().appendStatement(platformDdl.alterTableDropUniqueConstraint(constraint.getTableName(), constraint.getConstraintName()));
-
-    } else {
-      String[] cols = split(constraint.getColumnNames());
-      String[] nullableColumns = split(constraint.getNullableColumns());
-      writer.apply().appendStatement(platformDdl.alterTableAddUniqueConstraint(constraint.getTableName(), constraint.getConstraintName(), cols, nullableColumns));
+      } else {
+        String[] cols = split(constraint.getColumnNames());
+        String[] nullableColumns = split(constraint.getNullableColumns());
+        writer.apply().appendStatement(platformDdl.alterTableAddUniqueConstraint(constraint.getTableName(), constraint.getConstraintName(), cols, nullableColumns));
+      }
     }
   }
 

src/main/java/io/ebeaninternal/dbmigration/ddlgeneration/platform/SplitColumns.java

@@ -12,4 +12,13 @@ public class SplitColumns {
     return columns.split(",");
   }
 
+  /**
+   * Split returning null when columns is null or empty.
+   */
+  public static String[] splitWithNull(String columns) {
+    if (columns == null || columns.isEmpty()) {
+      return null;
+    }
+    return columns.split(",");
+  }
 }

src/main/java/io/ebeaninternal/dbmigration/migration/AddUniqueConstraint.java

@@ -21,6 +21,7 @@ import javax.xml.bind.annotation.XmlType;
  *       <attribute name="columnNames" use="required" type="{http://www.w3.org/2001/XMLSchema}string" />
  *       <attribute name="oneToOne" type="{http://www.w3.org/2001/XMLSchema}boolean" />
  *       <attribute name="nullableColumns" type="{http://www.w3.org/2001/XMLSchema}string" />
+ *       <attribute name="platforms" type="{http://www.w3.org/2001/XMLSchema}string" />
  *     </restriction>
  *   </complexContent>
  * </complexType>
@@ -41,6 +42,8 @@ public class AddUniqueConstraint {
   protected Boolean oneToOne;
   @XmlAttribute(name = "nullableColumns")
   protected String nullableColumns;
+  @XmlAttribute(name = "platforms")
+  protected String platforms;
 
   /**
    * Gets the value of the constraintName property.
@@ -142,4 +145,17 @@ public class AddUniqueConstraint {
     this.nullableColumns = value;
   }
 
+  /**
+   * Return the platforms.
+   */
+  public String getPlatforms() {
+    return platforms;
+  }
+
+  /**
+   * Set the platforms.
+   */
+  public void setPlatforms(String platforms) {
+    this.platforms = platforms;
+  }
 }

src/main/java/io/ebeaninternal/dbmigration/migration/CreateIndex.java

@@ -19,6 +19,7 @@ import javax.xml.bind.annotation.XmlType;
  *       <attribute name="indexName" use="required" type="{http://www.w3.org/2001/XMLSchema}string" />
  *       <attribute name="tableName" use="required" type="{http://www.w3.org/2001/XMLSchema}string" />
  *       <attribute name="columns" use="required" type="{http://www.w3.org/2001/XMLSchema}string" />
+ *       <attribute name="platforms" type="{http://www.w3.org/2001/XMLSchema}string" />
  *     </restriction>
  *   </complexContent>
  * </complexType>
@@ -35,6 +36,8 @@ public class CreateIndex {
   protected String tableName;
   @XmlAttribute(name = "columns", required = true)
   protected String columns;
+  @XmlAttribute(name = "platforms")
+  protected String platforms;
 
   /**
    * Gets the value of the indexName property.
@@ -96,4 +99,17 @@ public class CreateIndex {
     this.columns = value;
   }
 
+  /**
+   * Return the platforms.
+   */
+  public String getPlatforms() {
+    return platforms;
+  }
+
+  /**
+   * Set the platforms.
+   */
+  public void setPlatforms(String platforms) {
+    this.platforms = platforms;
+  }
 }

src/main/java/io/ebeaninternal/dbmigration/migration/DropIndex.java

@@ -18,6 +18,7 @@ import javax.xml.bind.annotation.XmlType;
  *     <restriction base="{http://www.w3.org/2001/XMLSchema}anyType">
  *       <attribute name="indexName" use="required" type="{http://www.w3.org/2001/XMLSchema}string" />
  *       <attribute name="tableName" use="required" type="{http://www.w3.org/2001/XMLSchema}string" />
+ *       <attribute name="platforms" type="{http://www.w3.org/2001/XMLSchema}string" />
  *     </restriction>
  *   </complexContent>
  * </complexType>
@@ -32,6 +33,8 @@ public class DropIndex {
   protected String indexName;
   @XmlAttribute(name = "tableName", required = true)
   protected String tableName;
+  @XmlAttribute(name = "platforms")
+  protected String platforms;
 
   /**
    * Gets the value of the indexName property.
@@ -73,4 +76,17 @@ public class DropIndex {
     this.tableName = value;
   }
 
+  /**
+   * Return the platforms.
+   */
+  public String getPlatforms() {
+    return platforms;
+  }
+
+  /**
+   * Set the platforms.
+   */
+  public void setPlatforms(String platforms) {
+    this.platforms = platforms;
+  }
 }

src/main/java/io/ebeaninternal/dbmigration/migration/UniqueConstraint.java

@@ -20,6 +20,7 @@ import javax.xml.bind.annotation.XmlType;
  *       <attribute name="columnNames" use="required" type="{http://www.w3.org/2001/XMLSchema}string" />
  *       <attribute name="oneToOne" type="{http://www.w3.org/2001/XMLSchema}boolean" />
  *       <attribute name="nullableColumns" type="{http://www.w3.org/2001/XMLSchema}string" />
+ *       <attribute name="platforms" type="{http://www.w3.org/2001/XMLSchema}string" />
  *     </restriction>
  *   </complexContent>
  * </complexType>
@@ -38,6 +39,8 @@ public class UniqueConstraint {
   protected Boolean oneToOne;
   @XmlAttribute(name = "nullableColumns")
   protected String nullableColumns;
+  @XmlAttribute(name = "platforms")
+  protected String platforms;
 
   /**
    * Gets the value of the name property.
@@ -119,4 +122,17 @@ public class UniqueConstraint {
     this.nullableColumns = value;
   }
 
+  /**
+   * Return the platforms.
+   */
+  public String getPlatforms() {
+    return platforms;
+  }
+
+  /**
+   * Set the platforms.
+   */
+  public void setPlatforms(String platforms) {
+    this.platforms = platforms;
+  }
 }

src/main/java/io/ebeaninternal/dbmigration/model/MCompoundUniqueConstraint.java

@@ -7,6 +7,9 @@ import io.ebeaninternal.dbmigration.migration.UniqueConstraint;
 import java.util.Arrays;
 import java.util.Objects;
 
+import static io.ebeaninternal.dbmigration.ddlgeneration.platform.SplitColumns.split;
+import static io.ebeaninternal.dbmigration.ddlgeneration.platform.SplitColumns.splitWithNull;
+
 /**
  * A unique constraint for multiple columns.
  * <p>
@@ -28,12 +31,41 @@ public class MCompoundUniqueConstraint {
    */
   private final String[] columns;
 
+  private final String platforms;
+
   private String[] nullableColumns;
 
-  public MCompoundUniqueConstraint(String[] columns, Boolean oneToOne, String name) {
+  /**
+   * Create for OneToOne.
+   */
+  public MCompoundUniqueConstraint(String[] columns, String name) {
     this.name = name;
     this.columns = columns;
-    this.oneToOne = Boolean.TRUE.equals(oneToOne);
+    this.oneToOne = true;
+    this.platforms = null;
+  }
+
+  public MCompoundUniqueConstraint(String[] columns, boolean oneToOne, String name, String platforms) {
+    this.name = name;
+    this.columns = columns;
+    this.oneToOne = oneToOne;
+    this.platforms = platforms;
+  }
+
+  public MCompoundUniqueConstraint(AddUniqueConstraint change) {
+    this.name = change.getConstraintName();
+    this.columns = split(change.getColumnNames());
+    this.oneToOne = change.isOneToOne();
+    this.platforms = change.getPlatforms();
+    this.nullableColumns = splitWithNull(change.getNullableColumns());
+  }
+
+  public MCompoundUniqueConstraint(UniqueConstraint uq) {
+    this.name = uq.getName();
+    this.columns = split(uq.getColumnNames());
+    this.oneToOne = uq.isOneToOne();
+    this.platforms = uq.getPlatforms();
+    this.nullableColumns = splitWithNull(uq.getNullableColumns());
   }
 
   /**
@@ -44,7 +76,7 @@ public class MCompoundUniqueConstraint {
   }
 
   /**
-   * Return true if this unqiue constraint is specifically for OneToOne mapping.
+   * Return true if this unique constraint is specifically for OneToOne mapping.
    */
   public boolean isOneToOne() {
     return oneToOne;
@@ -57,12 +89,17 @@ public class MCompoundUniqueConstraint {
     return name;
   }
 
+  public String getPlatforms() {
+    return platforms;
+  }
+
   public UniqueConstraint getUniqueConstraint() {
     UniqueConstraint uq = new UniqueConstraint();
     uq.setName(getName());
     uq.setColumnNames(join(columns));
     uq.setNullableColumns(join(nullableColumns));
     uq.setOneToOne(isOneToOne());
+    uq.setPlatforms(platforms);
     return uq;
   }
 
@@ -76,6 +113,7 @@ public class MCompoundUniqueConstraint {
     create.setColumnNames(join(columns));
     create.setNullableColumns(join(nullableColumns));
     create.setOneToOne(isOneToOne());
+    create.setPlatforms(platforms);
     return create;
   }
 
@@ -83,12 +121,13 @@ public class MCompoundUniqueConstraint {
    * Create a AddUniqueConstraint migration with 'DROP CONSTRAINT' set for this index.
    */
   public AddUniqueConstraint dropUniqueConstraint(String tableName) {
-    AddUniqueConstraint dropUniqueConstraint = new AddUniqueConstraint();
-    dropUniqueConstraint.setConstraintName(name);
-    dropUniqueConstraint.setTableName(tableName);
-    dropUniqueConstraint.setColumnNames(DdlHelp.DROP_CONSTRAINT);
-    dropUniqueConstraint.setNullableColumns(join(nullableColumns));
-    return dropUniqueConstraint;
+    AddUniqueConstraint drop = new AddUniqueConstraint();
+    drop.setConstraintName(name);
+    drop.setTableName(tableName);
+    drop.setColumnNames(DdlHelp.DROP_CONSTRAINT);
+    drop.setNullableColumns(join(nullableColumns));
+    drop.setPlatforms(platforms);
+    return drop;
   }
 
   public void setNullableColumns(String[] nullableColumns) {
@@ -127,9 +166,10 @@ public class MCompoundUniqueConstraint {
       return false;
     }
     MCompoundUniqueConstraint other = (MCompoundUniqueConstraint) obj;
-    return Arrays.equals(columns, other.columns)
-      && Arrays.equals(nullableColumns, other.nullableColumns)
+    // not including platforms in equals check
+    return oneToOne == other.oneToOne
       && Objects.equals(name, other.name)
-      && oneToOne == other.oneToOne;
+      && Arrays.equals(columns, other.columns)
+      && Arrays.equals(nullableColumns, other.nullableColumns);
   }
 }

src/main/java/io/ebeaninternal/dbmigration/model/MIndex.java

@@ -16,6 +16,8 @@ public class MIndex {
 
   private String indexName;
 
+  private String platforms;
+
   private List<String> columns = new ArrayList<>();
 
   /**
@@ -27,6 +29,11 @@ public class MIndex {
     this.columns.add(columnName);
   }
 
+  public MIndex(String indexName, String tableName, String[] columnNames, String platforms) {
+    this(indexName, tableName, columnNames);
+    this.platforms = platforms;
+  }
+
   /**
    * Create a multi column non unique index.
    */
@@ -40,6 +47,12 @@ public class MIndex {
     this.indexName = createIndex.getIndexName();
     this.tableName = createIndex.getTableName();
     this.columns = split(createIndex.getColumns());
+    this.platforms = createIndex.getPlatforms();
+  }
+
+  public String getKey() {
+    // currently indexName should be unique (not indexName + platforms)
+    return indexName;
   }
 
   /**
@@ -71,6 +84,7 @@ public class MIndex {
     create.setIndexName(indexName);
     create.setTableName(tableName);
     create.setColumns(join());
+    create.setPlatforms(platforms);
     return create;
   }
 
@@ -81,6 +95,7 @@ public class MIndex {
     DropIndex dropIndex = new DropIndex();
     dropIndex.setIndexName(indexName);
     dropIndex.setTableName(tableName);
+    dropIndex.setPlatforms(platforms);
     return dropIndex;
   }
 
@@ -88,7 +103,6 @@ public class MIndex {
    * Compare with an index of the same name.
    */
   public void compare(ModelDiff modelDiff, MIndex newIndex) {
-
     if (changed(newIndex)) {
       // drop and recreate the index
       modelDiff.addDropIndex(dropIndex());

src/main/java/io/ebeaninternal/dbmigration/model/MTable.java

@@ -27,6 +27,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import static io.ebeaninternal.dbmigration.ddlgeneration.platform.SplitColumns.split;
+
 /**
  * Holds the logical model for a given Table and everything associated to it.
  * <p>
@@ -173,11 +175,8 @@ public class MTable {
     for (Column column : cols) {
       addColumn(column);
     }
-    List<UniqueConstraint> uqConstraints = createTable.getUniqueConstraint();
-    for (UniqueConstraint uq : uqConstraints) {
-      MCompoundUniqueConstraint mUq = new MCompoundUniqueConstraint(SplitColumns.split(uq.getColumnNames()), uq.isOneToOne(), uq.getName());
-      mUq.setNullableColumns(SplitColumns.split(uq.getNullableColumns()));
-      uniqueConstraints.add(mUq);
+    for (UniqueConstraint uq : createTable.getUniqueConstraint()) {
+      uniqueConstraints.add(new MCompoundUniqueConstraint(uq));
     }
 
     for (ForeignKey fk : createTable.getForeignKey()) {
@@ -189,11 +188,10 @@ public class MTable {
     }
   }
 
-
   public void addForeignKey(String name, String refTableName, String indexName, String columnNames, String refColumnNames) {
     MCompoundForeignKey foreignKey = new MCompoundForeignKey(name, refTableName, indexName);
-    String[] cols = SplitColumns.split(columnNames);
-    String[] refCols = SplitColumns.split(refColumnNames);
+    String[] cols = split(columnNames);
+    String[] refCols = split(refColumnNames);
     for (int i = 0; i < cols.length && i < refCols.length; i++) {
       foreignKey.addColumnPair(cols[i], refCols[i]);
     }
@@ -597,19 +595,8 @@ public class MTable {
   /**
    * Add a unique constraint.
    */
-  public void addUniqueConstraint(String[] columns, boolean oneToOne, String constraintName) {
-    uniqueConstraints.add(new MCompoundUniqueConstraint(columns, oneToOne, constraintName));
-  }
-
-  /**
-   * Add a unique constraint.
-   */
-  public void addUniqueConstraint(List<MColumn> columns, boolean oneToOne, String constraintName) {
-    String[] cols = new String[columns.size()];
-    for (int i = 0; i < columns.size(); i++) {
-      cols[i] = columns.get(i).getName();
-    }
-    addUniqueConstraint(cols, oneToOne, constraintName);
+  public void addUniqueConstraint(MCompoundUniqueConstraint uniqueConstraint) {
+    uniqueConstraints.add(uniqueConstraint);
   }
 
   /**

src/main/java/io/ebeaninternal/dbmigration/model/ModelContainer.java

@@ -2,7 +2,6 @@ package io.ebeaninternal.dbmigration.model;
 
 import io.ebean.migration.MigrationVersion;
 import io.ebeaninternal.dbmigration.ddlgeneration.platform.DdlHelp;
-import io.ebeaninternal.dbmigration.ddlgeneration.platform.SplitColumns;
 import io.ebeaninternal.dbmigration.migration.AddColumn;
 import io.ebeaninternal.dbmigration.migration.AddHistoryTable;
 import io.ebeaninternal.dbmigration.migration.AddTableComment;
@@ -21,6 +20,7 @@ import io.ebeaninternal.dbmigration.migration.Migration;
 import io.ebeaninternal.dbmigration.migration.Sql;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
@@ -82,13 +82,6 @@ public class ModelContainer {
     return tables;
   }
 
-  /**
-   * Return the map of all the non unique non fk indexes.
-   */
-  public Map<String, MIndex> getIndexes() {
-    return indexes;
-  }
-
   /**
    * Return the table by name.
    */
@@ -97,10 +90,21 @@ public class ModelContainer {
   }
 
   /**
-   * Return the index by name.
+   * Lookup the matching index during DIFF migration processing.
    */
-  public MIndex getIndex(String indexName) {
-    return indexes.get(indexName);
+  public MIndex getIndex(MIndex newIndex) {
+    return indexes.get(newIndex.getKey());
+  }
+
+  public Collection<MIndex> allIndexes() {
+    return indexes.values();
+  }
+
+  /**
+   * Return true if the index does not exist and should be dropped.
+   */
+  public boolean dropIndex(MIndex existingIndex) {
+    return !indexes.containsKey(existingIndex.getKey());
   }
 
   /**
@@ -201,10 +205,7 @@ public class ModelContainer {
     if (DdlHelp.isDropConstraint(change.getColumnNames())) {
       table.getUniqueConstraints().removeIf(constraint -> constraint.getName().equals(change.getConstraintName()));
     } else {
-      MCompoundUniqueConstraint constraint = new MCompoundUniqueConstraint(
-          SplitColumns.split(change.getColumnNames()), change.isOneToOne(), change.getConstraintName());
-      constraint.setNullableColumns(SplitColumns.split(change.getNullableColumns()));
-      table.getUniqueConstraints().add(constraint);
+      table.getUniqueConstraints().add(new MCompoundUniqueConstraint(change));
     }
   }
 
@@ -216,8 +217,7 @@ public class ModelContainer {
     if (DdlHelp.isDropForeignKey(change.getColumnNames())) {
       table.removeForeignKey(change.getName());
     } else {
-      table.addForeignKey(change.getName(), change.getRefTableName(), change.getIndexName(), change.getColumnNames(),
-          change.getRefColumnNames());
+      table.addForeignKey(change.getName(), change.getRefTableName(), change.getIndexName(), change.getColumnNames(), change.getRefColumnNames());
     }
   }
 
@@ -259,7 +259,8 @@ public class ModelContainer {
     if (indexes.containsKey(indexName)) {
       throw new IllegalStateException("Index [" + indexName + "] already exists in model?");
     }
-    indexes.put(createIndex.getIndexName(), new MIndex(createIndex));
+    MIndex index = new MIndex(createIndex);
+    indexes.put(index.getKey(), index);
   }
 
   /**
@@ -321,7 +322,7 @@ public class ModelContainer {
     if (reusedElementCollection != null) {
       final MIndex index = reusedElementCollection.setReusedElementCollection();
       if (index != null) {
-        indexes.put(index.getIndexName(), index);
+        indexes.put(index.getKey(), index);
       }
     } else {
       if (table.isPartitioned()) {
@@ -332,17 +333,10 @@ public class ModelContainer {
   }
 
   /**
-   * Add a single column index.
+   * Add an index.
    */
-  public void addIndex(String indexName, String tableName, String columnName) {
-    indexes.put(indexName, new MIndex(indexName, tableName, columnName));
-  }
-
-  /**
-   * Add a multi column index.
-   */
-  public void addIndex(String indexName, String tableName, String[] columnNames) {
-    indexes.put(indexName, new MIndex(indexName, tableName, columnNames));
+  public void addIndex(MIndex index) {
+    indexes.put(index.getKey(), index);
   }
 
   /**

src/main/java/io/ebeaninternal/dbmigration/model/ModelDiff.java

@@ -140,9 +140,8 @@ public class ModelDiff {
       }
     }
 
-    Map<String, MIndex> newIndexes = newModel.getIndexes();
-    for (MIndex newIndex : newIndexes.values()) {
-      MIndex currentIndex = baseModel.getIndex(newIndex.getIndexName());
+    for (MIndex newIndex : newModel.allIndexes()) {
+      MIndex currentIndex = baseModel.getIndex(newIndex);
       if (currentIndex == null) {
         addCreateIndex(newIndex.createIndex());
       } else {
@@ -151,8 +150,8 @@ public class ModelDiff {
     }
 
     // search for indexes that are no longer used
-    for (MIndex existingIndex : baseModel.getIndexes().values()) {
-      if (!newIndexes.containsKey(existingIndex.getIndexName())) {
+    for (MIndex existingIndex : baseModel.allIndexes()) {
+      if (newModel.dropIndex(existingIndex)) {
         addDropIndex(existingIndex.dropIndex());
       }
     }

src/main/java/io/ebeaninternal/dbmigration/model/build/ModelBuildContext.java

@@ -7,6 +7,7 @@ import io.ebean.config.dbplatform.DbPlatformTypeMapping;
 import io.ebeaninternal.dbmigration.ddlgeneration.platform.DefaultConstraintMaxLength;
 import io.ebeaninternal.dbmigration.model.MColumn;
 import io.ebeaninternal.dbmigration.model.MCompoundForeignKey;
+import io.ebeaninternal.dbmigration.model.MIndex;
 import io.ebeaninternal.dbmigration.model.MTable;
 import io.ebeaninternal.dbmigration.model.ModelContainer;
 import io.ebeaninternal.server.deploy.BeanDescriptor;
@@ -125,12 +126,8 @@ public class ModelBuildContext {
     model.addTableElementCollection(table);
   }
 
-  public void addIndex(String indexName, String tableName, String columnName) {
-    model.addIndex(indexName, tableName, columnName);
-  }
-
-  public void addIndex(String indexName, String tableName, String[] columnNames) {
-    model.addIndex(indexName, tableName, columnNames);
+  public void addIndex(MIndex index) {
+    model.addIndex(index);
   }
 
   /**

src/main/java/io/ebeaninternal/dbmigration/model/build/ModelBuildPropertyVisitor.java

@@ -1,8 +1,11 @@
 package io.ebeaninternal.dbmigration.model.build;
 
+import io.ebean.annotation.Platform;
 import io.ebeaninternal.dbmigration.ddlgeneration.platform.util.IndexSet;
 import io.ebeaninternal.dbmigration.model.MColumn;
 import io.ebeaninternal.dbmigration.model.MCompoundForeignKey;
+import io.ebeaninternal.dbmigration.model.MCompoundUniqueConstraint;
+import io.ebeaninternal.dbmigration.model.MIndex;
 import io.ebeaninternal.dbmigration.model.MTable;
 import io.ebeaninternal.dbmigration.model.visitor.BaseTablePropertyVisitor;
 import io.ebeaninternal.server.deploy.BeanDescriptor;
@@ -20,6 +23,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.Set;
+import java.util.StringJoiner;
 
 /**
  * Used as part of ModelBuildBeanVisitor and generally adds the MColumn to the associated
@@ -42,7 +46,6 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
   private int countUnique;
   private int countCheck;
 
-
   public ModelBuildPropertyVisitor(ModelBuildContext ctx, MTable table, BeanDescriptor<?> beanDescriptor) {
     this.ctx = ctx;
     this.table = table;
@@ -54,31 +57,55 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
    * Add unique constraints defined via JPA UniqueConstraint annotations.
    */
   private void addIndexes(IndexDefinition[] indexes) {
-
     if (indexes != null) {
       for (IndexDefinition index : indexes) {
         String[] columns = index.getColumns();
         indexSet.add(columns);
-
         if (index.isUnique()) {
-          String uqName = index.getName();
-          if (uqName == null || uqName.trim().isEmpty()) {
-            uqName = determineUniqueConstraintName(columns);
-          }
-          table.addUniqueConstraint(columns, false, uqName);
-
+          table.addUniqueConstraint(createMUniqueConstraint(index, columns));
         } else {
           // 'just' an index (not a unique constraint)
-          String idxName = index.getName();
-          if (idxName == null || idxName.trim().isEmpty()) {
-            idxName = determineIndexName(columns);
-          }
-          ctx.addIndex(idxName, table.getName(), columns);
+          ctx.addIndex(createMIndex(indexName(index), table.getName(), index));
         }
       }
     }
   }
 
+  private MCompoundUniqueConstraint createMUniqueConstraint(IndexDefinition index, String[] columns) {
+    return new MCompoundUniqueConstraint(columns, false, uniqueConstraintName(index), platforms(index.getPlatforms()));
+  }
+
+  private String uniqueConstraintName(IndexDefinition index) {
+    String uqName = index.getName();
+    if (uqName == null || uqName.trim().isEmpty()) {
+      return determineUniqueConstraintName(index.getColumns());
+    }
+    return uqName;
+  }
+
+  private String indexName(IndexDefinition index) {
+    String idxName = index.getName();
+    if (idxName == null || idxName.trim().isEmpty()) {
+      idxName = determineIndexName(index.getColumns());
+    }
+    return idxName;
+  }
+
+  private MIndex createMIndex(String indexName, String tableName, IndexDefinition index) {
+    return new MIndex(indexName, tableName, index.getColumns(), platforms(index.getPlatforms()));
+  }
+
+  private String platforms(Platform[] platforms) {
+    if (platforms == null || platforms.length == 0) {
+      return null;
+    }
+    StringJoiner joiner = new StringJoiner(",");
+    for (Platform platform : platforms) {
+      joiner.add(platform.name());
+    }
+    return joiner.toString();
+  }
+
   @Override
   public void visitEnd() {
 
@@ -105,7 +132,6 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
     }
 
     addDraftTable();
-
     table.updateCompoundIndices();
   }
 
@@ -146,9 +172,8 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
 
   @Override
   public void visitEmbeddedScalar(BeanProperty p, BeanPropertyAssocOne<?> embedded) {
-
     if (p instanceof BeanPropertyAssocOne) {
-      visitOneImported((BeanPropertyAssocOne)p);
+      visitOneImported((BeanPropertyAssocOne<?>)p);
     } else {
       visitScalar(p);
     }
@@ -222,13 +247,13 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
       // for MsSqlServer we need different DDL to handle NULL values on this constraint
       if (modelColumns.size() == 1) {
         MColumn col = modelColumns.get(0);
-        col.setUniqueOneToOne(determineUniqueConstraintName(col.getName()));
         indexSetAdd(col.getName());
+        col.setUniqueOneToOne(determineUniqueConstraintName(col.getName()));
 
       } else {
+        String[] cols = indexSetAdd(toColumnNames(modelColumns));
         String uqName = determineUniqueConstraintName(p.getName());
-        table.addUniqueConstraint(modelColumns, true, uqName);
-        indexSetAdd(modelColumns);
+        table.addUniqueConstraint(new MCompoundUniqueConstraint(cols, uqName));
       }
     }
   }
@@ -313,19 +338,23 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
     indexSet.add(column);
   }
 
-  private void indexSetAdd(List<MColumn> modelColumns) {
+  private String[] indexSetAdd(String[] cols) {
+    indexSet.add(cols);
+    return cols;
+  }
+
+  private String[] toColumnNames(List<MColumn> modelColumns) {
     String[] cols = new String[modelColumns.size()];
     for (int i = 0; i < modelColumns.size(); i++) {
       cols[i] = modelColumns.get(i).getName();
     }
-    indexSet.add(cols);
+    return cols;
   }
 
   /**
    * Return the primary key constraint name.
    */
   protected String determinePrimaryKeyName() {
-
     return ctx.primaryKeyName(table.getName());
   }
 
@@ -333,12 +362,10 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
    * Return the foreign key constraint name given a single column foreign key.
    */
   protected String determineForeignKeyConstraintName(String columnName) {
-
     return ctx.foreignKeyConstraintName(table.getName(), columnName, ++countForeignKey);
   }
 
   protected String determineForeignKeyIndexName(String column) {
-
     String[] cols = {column};
     return determineForeignKeyIndexName(cols);
   }
@@ -347,7 +374,6 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
    * Return the foreign key constraint name given a single column foreign key.
    */
   protected String determineForeignKeyIndexName(String[] columns) {
-
     return ctx.foreignKeyIndexName(table.getName(), columns, ++countIndex);
   }
 
@@ -355,7 +381,6 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
    * Return the index name given a single column foreign key.
    */
   protected String determineIndexName(String column) {
-
     return ctx.indexName(table.getName(), column, ++countIndex);
   }
 
@@ -363,7 +388,6 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
    * Return the index name given multiple columns.
    */
   protected String determineIndexName(String[] columns) {
-
     return ctx.indexName(table.getName(), columns, ++countIndex);
   }
 
@@ -371,7 +395,6 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
    * Return the unique constraint name.
    */
   protected String determineUniqueConstraintName(String columnName) {
-
     return ctx.uniqueConstraintName(table.getName(), columnName, ++countUnique);
   }
 
@@ -379,7 +402,6 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
    * Return the unique constraint name.
    */
   protected String determineUniqueConstraintName(String[] columnNames) {
-
     return ctx.uniqueConstraintName(table.getName(), columnNames, ++countUnique);
   }
 
@@ -387,11 +409,9 @@ public class ModelBuildPropertyVisitor extends BaseTablePropertyVisitor {
    * Return the constraint name.
    */
   protected String determineCheckConstraintName(String columnName) {
-
     return ctx.checkConstraintName(table.getName(), columnName, ++countCheck);
   }
 
-
   private boolean hasValue(String val) {
     return val != null && !val.isEmpty();
   }

src/main/java/io/ebeaninternal/server/deploy/IndexDefinition.java

@@ -1,5 +1,7 @@
 package io.ebeaninternal.server.deploy;
 
+import io.ebean.annotation.Platform;
+
 /**
  * Holds multiple column unique constraints defined for an entity.
  */
@@ -9,12 +11,18 @@ public class IndexDefinition {
 
   private final String name;
 
+  private final Platform[] platforms;
+
   private final boolean unique;
 
-  public IndexDefinition(String[] columns, String name, boolean unique) {
+  /**
+   * Create from Index annotation.
+   */
+  public IndexDefinition(String[] columns, String name, boolean unique, Platform[] platforms) {
     this.columns = columns;
     this.unique = unique;
     this.name = name;
+    this.platforms = platforms;
   }
 
   /**
@@ -24,6 +32,7 @@ public class IndexDefinition {
     this.columns = columns;
     this.unique = true;
     this.name = null;
+    this.platforms = null;
   }
 
   /**
@@ -47,4 +56,10 @@ public class IndexDefinition {
     return columns;
   }
 
+  /**
+   * Return the platforms this index applies to.
+   */
+  public Platform[] getPlatforms() {
+    return platforms;
+  }
 }

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationClass.java

@@ -134,7 +134,7 @@ public class AnnotationClass extends AnnotationParser {
     }
 
     for (Index index : findAnnotationsRecursive(cls, Index.class)) {
-      descriptor.addIndex(new IndexDefinition(convertColumnNames(index.columnNames()), index.name(), index.unique()));
+      descriptor.addIndex(new IndexDefinition(convertColumnNames(index.columnNames()), index.name(), index.unique(), index.platforms()));
     }
 
     UniqueConstraint uc = findAnnotationRecursive(cls, UniqueConstraint.class);

src/main/java/io/ebeaninternal/server/deploy/parse/AnnotationFields.java

@@ -416,7 +416,7 @@ public class AnnotationFields extends AnnotationParser {
     if (columnNames.length == 1 && hasRelationshipItem(prop)) {
       throw new RuntimeException("Can't use Index on foreign key relationships.");
     }
-    descriptor.addIndex(new IndexDefinition(columnNames, index.name(), index.unique()));
+    descriptor.addIndex(new IndexDefinition(columnNames, index.name(), index.unique(), index.platforms()));
   }
 
   private void readJsonAnnotations(DeployBeanProperty prop) {