From 93f802f7fee4efd6ce4300bf59e6609a00712b97 Mon Sep 17 00:00:00 2001
From: Robin Bygrave <robin.bygrave@gmail.com>
Date: Thu, 6 Aug 2015 13:37:51 +1200
Subject: [PATCH]  #374 - Drop foreign keys before indexes

---
 .../avaje/ebean/dbmigration/DdlGenerator.java    |  2 +-
 .../ddlgeneration/platform/BaseTableDdl.java     | 11 +++++------
 .../ddlgeneration/platform/MySqlDdl.java         | 16 +++++++++++++---
 .../ddlgeneration/platform/PlatformDdl.java      | 13 +++++++++++--
 .../createTable-rollbackFirst.txt                |  2 +-
 5 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/src/main/java/com/avaje/ebean/dbmigration/DdlGenerator.java b/src/main/java/com/avaje/ebean/dbmigration/DdlGenerator.java
index b49991227..637059d27 100644
--- a/src/main/java/com/avaje/ebean/dbmigration/DdlGenerator.java
+++ b/src/main/java/com/avaje/ebean/dbmigration/DdlGenerator.java
@@ -254,7 +254,7 @@ public class DdlGenerator implements SpiEbeanPlugin {
         stmt = stmt.substring(0, stmt.length() - 1);
       }
 
-      logger.trace("executing " + oneOf + " " + getSummary(stmt));
+      logger.info("executing " + oneOf + " " + getSummary(stmt));
 
       pstmt = c.prepareStatement(stmt);
       pstmt.execute();
diff --git a/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/BaseTableDdl.java b/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/BaseTableDdl.java
index a38faa0ca..67d5fed15 100644
--- a/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/BaseTableDdl.java
+++ b/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/BaseTableDdl.java
@@ -215,17 +215,16 @@ public class BaseTableDdl implements TableDdl {
 
     fkeyBuffer.end();
 
+    write.rollbackForeignKeys()
+        .append(platformDdl.alterTableDropForeignKey(tableName, fkName))
+        .endOfStatement();
+
     if (addIndex) {
       write.rollbackForeignKeys()
-          .append("drop index ").append(indexName)
+          .append(platformDdl.dropIndex(indexName, tableName))
           .endOfStatement();
     }
 
-    write.rollbackForeignKeys()
-        .append("alter table ").append(tableName).append(" ")
-        .append(platformDdl.dropForeignKeyConstraint(fkName))
-        .endOfStatement();
-
     write.rollbackForeignKeys().end();
 
   }
diff --git a/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/MySqlDdl.java b/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/MySqlDdl.java
index 9a1f48517..d6ac50120 100644
--- a/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/MySqlDdl.java
+++ b/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/MySqlDdl.java
@@ -13,9 +13,19 @@ public class MySqlDdl extends PlatformDdl {
     this.namingConvention.maxConstraintNameLength = 64;
   }
 
-
+  /**
+   * Return the drop index statement.
+   */
   @Override
-  public String dropForeignKeyConstraint(String fkName) {
-    return "drop foreign key " + fkName;
+  public String dropIndex(String indexName, String tableName) {
+    return "drop index " + indexName + " on " + tableName;
   }
+
+  /**
+   * Return the drop foreign key clause.
+   */
+  public String alterTableDropForeignKey(String tableName, String fkName) {
+    return "alter table " + tableName + " drop foreign key " + fkName;
+  }
+
 }
diff --git a/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/PlatformDdl.java b/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/PlatformDdl.java
index 0c2973aa3..69c756249 100644
--- a/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/PlatformDdl.java
+++ b/src/main/java/com/avaje/ebean/dbmigration/ddlgeneration/platform/PlatformDdl.java
@@ -79,8 +79,8 @@ public class PlatformDdl {
   /**
    * Return the drop foreign key clause.
    */
-  public String dropForeignKeyConstraint(String fkName) {
-    return "drop constraint "+fkName;
+  public String alterTableDropForeignKey(String tableName, String fkName) {
+    return "alter table " + tableName + " drop constraint " + fkName;
   }
 
   /**
@@ -131,6 +131,13 @@ public class PlatformDdl {
     return dropTableIfExists + tableName + dropTableCascade;
   }
 
+  /**
+   * Return the drop index statement.
+   */
+  public String dropIndex(String indexName, String tableName) {
+    return "drop index "+indexName;
+  }
+
   /**
    * Support lower naming tables and columns in DDL generation.
    * Tables/Columns with quoted identifiers are exempt.
@@ -148,4 +155,6 @@ public class PlatformDdl {
   public int getMaxTableNameLength() {
     return namingConvention.getMaxTableNameLength();
   }
+
+
 }
diff --git a/src/test/resources/assert/BaseTableDdlTest/createTable-rollbackFirst.txt b/src/test/resources/assert/BaseTableDdlTest/createTable-rollbackFirst.txt
index a6c9768a1..3534ef19b 100644
--- a/src/test/resources/assert/BaseTableDdlTest/createTable-rollbackFirst.txt
+++ b/src/test/resources/assert/BaseTableDdlTest/createTable-rollbackFirst.txt
@@ -1,3 +1,3 @@
-drop index ix_mytable_order_id;
 alter table mytable drop constraint fk_mytable_order_id;
+drop index ix_mytable_order_id;