#559 - DDL - DB Migration refactor - remove rollback.ddl generation (ultimately not used by FlywayDb etc)

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>
@@ -61,21 +56,8 @@ public class DbMigrationConfig {
    */
   protected String modelPath = "model";
 
-  /**
-   * Subdirectory the rollback ddl scripts go into.
-   */
-  protected String rollbackPath = "rollback";
-
-  /**
-   * Apply script suffix.
-   */
   protected String applySuffix = ".sql";
 
-  /**
-   * 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;
@@ -135,20 +117,6 @@ public class DbMigrationConfig {
     this.modelPath = modelPath;
   }
 
-  /**
-   * 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)
    */
@@ -163,20 +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).
    */
@@ -191,20 +145,6 @@ public class DbMigrationConfig {
     this.applySuffix = applySuffix;
   }
 
-  /**
-   * 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.
    */
@@ -256,7 +196,6 @@ public class DbMigrationConfig {
    * into a single directory.
    */
   public void singleDirectory() {
-    this.rollbackPath = "";
     this.modelPath = "";
   }
 
@@ -270,16 +209,13 @@ public class DbMigrationConfig {
       singleDirectory();
     } else {
       modelPath = properties.get("migration.modelPath", modelPath);
-      rollbackPath = properties.get("migration.rollbackPath", rollbackPath);
     }
     applySuffix = properties.get("migration.applySuffix", applySuffix);
-    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);

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

@@ -10,11 +10,6 @@ import com.avaje.ebean.dbmigration.model.ModelContainer;
  */
 public class DdlWrite {
 
-  public enum Mode {
-    APPLY,
-    ROLLBACK
-  }
-
   private final ModelContainer currentModel;
 
   private final DdlBuffer applyDropDependencies;
@@ -25,11 +20,9 @@ public class DdlWrite {
 
   private final DdlBuffer applyHistory;
 
-  private final DdlBuffer rollbackDropDependencies;
+  private final DdlBuffer dropAllForeignKeys;
 
-  private final DdlBuffer rollbackForeignKeys;
-
-  private final DdlBuffer rollback;
+  private final DdlBuffer dropAll;
 
   /**
    * Create without any configuration or current model (no history support).
@@ -47,9 +40,8 @@ public class DdlWrite {
     this.apply = new BaseDdlBuffer(configuration);
     this.applyForeignKeys = new BaseDdlBuffer(configuration);
     this.applyHistory = new BaseDdlBuffer(configuration);
-    this.rollbackDropDependencies = new BaseDdlBuffer(configuration);
-    this.rollbackForeignKeys = new BaseDdlBuffer(configuration);
-    this.rollback = new BaseDdlBuffer(configuration);
+    this.dropAllForeignKeys = new BaseDdlBuffer(configuration);
+    this.dropAll = new BaseDdlBuffer(configuration);
   }
 
   /**
@@ -73,52 +65,6 @@ public class DdlWrite {
         && applyDropDependencies.getBuffer().isEmpty();
   }
 
-  /**
-   * Return true if the apply rollback buffers are all empty.
-   */
-  public boolean isApplyRollbackEmpty() {
-    return rollback.getBuffer().isEmpty()
-        && rollbackForeignKeys.getBuffer().isEmpty()
-        && rollbackDropDependencies.getBuffer().isEmpty();
-  }
-
-  /**
-   * Return the apply or rollback buffer.
-   */
-  public DdlBuffer buffer(Mode mode) {
-    switch (mode) {
-      case APPLY: return apply();
-      case ROLLBACK: return rollback();
-      default:
-        throw new IllegalStateException("Invalid mode" + mode);
-    }
-  }
-
-  /**
-   * Return the apply or rollback buffer.
-   */
-  public DdlBuffer historyBuffer(Mode mode) {
-    switch (mode) {
-      case APPLY: return applyHistory();
-      case ROLLBACK: return rollback();
-      default:
-        throw new IllegalStateException("Invalid mode" + mode);
-    }
-  }
-
-  /**
-   * Return the apply or rollback drop dependencies buffer.
-   */
-  public DdlBuffer dropDependencies(Mode mode) {
-
-    switch (mode) {
-      case APPLY: return applyDropDependencies();
-      case ROLLBACK: return rollbackDropDependencies();
-      default:
-        throw new IllegalStateException("Invalid mode" + mode);
-    }
-  }
-
   /**
    * Return the buffer that APPLY DDL is written to.
    */
@@ -151,32 +97,17 @@ public class DdlWrite {
   }
 
   /**
-   * Return the buffer that rollback executes early to drop dependencies like views.
+   * Return the buffer used for the 'drop all DDL' for dropping foreign keys and associated indexes.
    */
-  public DdlBuffer rollbackDropDependencies() {
-    return rollbackDropDependencies;
+  public DdlBuffer dropAllForeignKeys() {
+    return dropAllForeignKeys;
   }
 
   /**
-   * Return the buffer that ROLLBACK DDL is written to for foreign keys and associated indexes.
+   * Return the buffer used for the 'drop all DDL' to drop tables, views and history triggers etc.
    */
-  public DdlBuffer rollbackForeignKeys() {
-    return rollbackForeignKeys;
-  }
-
-  /**
-   * 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.
-   */
-  public DdlBuffer rollback() {
-    return rollback;
+  public DdlBuffer dropAll() {
+    return dropAll;
   }
 
 }

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();
   }
 
   /**
@@ -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

@@ -69,31 +69,17 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
    */
   protected void updateTriggers(DdlWrite writer, MTable table, HistoryTableUpdate update) throws IOException {
 
-    DbTriggerUpdate triggerUpdate = createDbTriggerUpdate(writer, table);
+    writer.applyHistory().append("-- changes: ").append(update.description()).newLine();
 
-    String description = update.description();
-    List<String> includedColumns = columnNamesForApply(table);
-
-    DdlBuffer apply = writer.applyHistory();
-    apply.append("-- changes: ").append(description).newLine();
-
-    triggerUpdate.prepare(DdlWrite.Mode.APPLY, includedColumns);
-    updateHistoryTriggers(triggerUpdate);
-
-    // put a reverted version into the rollback buffer
-    update.toRevertedColumns(includedColumns);
-
-    DdlBuffer rollback = writer.rollback();
-    rollback.append("-- revert changes: ").append(description).newLine();
-
-    triggerUpdate.prepare(DdlWrite.Mode.ROLLBACK, includedColumns);
-    updateHistoryTriggers(triggerUpdate);
+    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);
+    return new DbTriggerUpdate(baseTableName, historyTableName, writer, columns);
   }
 
   @Override
@@ -124,9 +110,8 @@ 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);
     createStoredFunction(writer, table);
@@ -295,7 +280,7 @@ public abstract class DbTriggerBasedHistoryDdl implements PlatformHistoryDdl {
    * the column.
    * </p>
    */
-  protected List<String> columnNamesForApply(MTable table) throws IOException {
+  protected List<String> columnNamesForApply(MTable table) {
 
     return table.allHistoryColumns(true);
   }

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

@@ -16,36 +16,27 @@ public class DbTriggerUpdate {
 
   private final DdlWrite writer;
 
-  private DdlWrite.Mode mode;
+  private final List<String> columns;
 
-  private List<String> includedColumns;
-
-  public DbTriggerUpdate(String baseTableName, String historyTableName, DdlWrite writer) {
+  public DbTriggerUpdate(String baseTableName, String historyTableName, DdlWrite writer, List<String> columns) {
     this.baseTableName = baseTableName;
     this.historyTableName = historyTableName;
     this.writer = writer;
-  }
-
-  /**
-   * Prepare for use given the mode and columns included in history.
-   */
-  public void prepare(DdlWrite.Mode mode, List<String> includedColumns) {
-    this.mode = mode;
-    this.includedColumns = includedColumns;
+    this.columns = columns;
   }
 
   /**
    * Return the appropriate buffer for the current mode.
    */
   public DdlBuffer historyBuffer() {
-    return writer.historyBuffer(mode);
+    return writer.applyHistory();
   }
 
   /**
    * Return the appropriate drop dependency buffer for the current mode.
    */
   public DdlBuffer dropDependencyBuffer() {
-    return writer.dropDependencies(mode);
+    return writer.applyDropDependencies();
   }
 
   /**
@@ -66,7 +57,7 @@ public class DbTriggerUpdate {
    * Return the included columns.
    */
   public List<String> getColumns() {
-    return includedColumns;
+    return columns;
   }
 
 }

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

@@ -39,22 +39,6 @@ public class HistoryTableUpdate {
       return change.name().toLowerCase()+" "+column;
     }
 
-    private void revert(List<String> includedColumns) {
-      switch (change) {
-        case ADD:
-        case INCLUDE: {
-          includedColumns.remove(column);
-          break;
-        }
-        case EXCLUDE:
-        case DROP: {
-          includedColumns.add(column);
-          break;
-        }
-        default:
-          throw new IllegalStateException("Unexpected change "+change);
-      }
-    }
   }
 
   private final String baseTable;
@@ -76,17 +60,6 @@ public class HistoryTableUpdate {
     return columnChanges.toString();
   }
 
-  /**
-   * Reverse the apply changes which equates to removing any newly added or
-   * included columns.
-   */
-  public void toRevertedColumns(List<String> includedColumns) {
-
-    for (Column columnChange : columnChanges) {
-      columnChange.revert(includedColumns);
-    }
-  }
-
   /**
    * Add a comment for column added, dropped, included or excluded.
    */

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

@@ -27,8 +27,6 @@ public class MySqlHistoryDdl extends DbTriggerBasedHistoryDdl {
 
     DbTriggerUpdate update = createDbTriggerUpdate(writer, table);
 
-    update.prepare(DdlWrite.Mode.APPLY, columnNamesForApply(table));
-
     addBeforeUpdate(updateTriggerName(update.getBaseTable()), update);
     addBeforeDelete(deleteTriggerName(update.getBaseTable()), update);
   }

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();
   }

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

@@ -74,18 +74,7 @@ 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();
-        }
-      }
     }
-
   }
 
   protected FileWriter createWriter(File path, String fullVersion, String subPath, String suffix) throws IOException {
@@ -123,18 +112,6 @@ public class PlatformDdlWriter {
     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
-    prependDropDependencies(writer, write.rollbackDropDependencies());
-    writer.append("-- reverse changes\n");
-    writer.append(write.rollbackForeignKeys().getBuffer());
-    writer.append(write.rollback().getBuffer());
-  }
-
   private void prependDropDependencies(Writer writer, DdlBuffer buffer) throws IOException {
     if (!buffer.isEmpty()) {
       writer.append("-- drop dependencies\n");