Merge pull request #1092 from grandinj/230_fkconstraint

#230: Renaming a column does not update foreign key  constraint

h2/src/docsrc/html/changelog.html

@@ -21,6 +21,8 @@ Change Log
 
 <h2>Next Version (unreleased)</h2>
 <ul>
+<li>Issue #230: Renaming a column does not update foreign key constraint 
+</li>
 <li>Issue #394: Recover tool places COLLATION and BINARY_COLLATION after temporary tables
 </li>
 <li>Improve the script-based unit testing to check the error code of the exception thrown. 

h2/src/main/org/h2/command/ddl/AlterTableRenameColumn.java

@@ -7,6 +7,7 @@ package org.h2.command.ddl;
 
 import org.h2.api.ErrorCode;
 import org.h2.command.CommandInterface;
+import org.h2.constraint.ConstraintReferential;
 import org.h2.engine.Database;
 import org.h2.engine.DbObject;
 import org.h2.engine.Right;
@@ -62,6 +63,7 @@ public class AlterTableRenameColumn extends SchemaCommand {
         Column column = table.getColumn(oldName);
         session.getUser().checkRight(table, Right.ALL);
         table.checkSupportAlter();
+
         // we need to update CHECK constraint
         // since it might reference the name of the column
         Expression newCheckExpr = column.getCheckConstraint(session, newName);
@@ -70,6 +72,15 @@ public class AlterTableRenameColumn extends SchemaCommand {
         column.addCheckConstraint(session, newCheckExpr);
         table.setModified();
         db.updateMeta(session, table);
+
+        // if we have foreign key constraints pointing at this table, we need to update them
+        for (DbObject childDbObject : table.getChildren()) {
+            if (childDbObject instanceof ConstraintReferential) {
+                ConstraintReferential ref = (ConstraintReferential) childDbObject;
+                ref.updateOnTableColumnRename();
+            }
+        }
+
         for (DbObject child : table.getChildren()) {
             if (child.getCreateSQL() != null) {
                 db.updateMeta(session, child);

h2/src/main/org/h2/constraint/ConstraintReferential.java

@@ -470,6 +470,17 @@ public class ConstraintReferential extends Constraint {
         buildDeleteSQL();
     }
 
+    public void updateOnTableColumnRename() {
+        if (deleteAction != null) {
+            deleteSQL = null;
+            buildDeleteSQL();
+        }
+        if (updateAction != null) {
+            updateSQL = null;
+            buildUpdateSQL();
+        }
+    }
+
     private void buildDeleteSQL() {
         if (deleteAction == ConstraintActionType.RESTRICT) {
             return;

h2/src/main/org/h2/table/Table.java

@@ -85,6 +85,7 @@ public abstract class Table extends SchemaObjectBase {
      */
     private final CopyOnWriteArrayList<TableView> dependentViews = new CopyOnWriteArrayList<>();
     private ArrayList<TableSynonym> synonyms;
+    /** Is foreign key constraint checking enabled for this table. */
     private boolean checkForeignKeyConstraints = true;
     private boolean onCommitDrop, onCommitTruncate;
     private volatile Row nullRow;
@@ -1065,6 +1066,9 @@ public abstract class Table extends SchemaObjectBase {
         checkForeignKeyConstraints = enabled;
     }
 
+    /**
+     * @return is foreign key constraint checking enabled for this table.
+     */
     public boolean getCheckForeignKeyConstraints() {
         return checkForeignKeyConstraints;
     }

h2/src/test/org/h2/test/scripts/TestScript.java

@@ -92,6 +92,7 @@ public class TestScript extends TestBase {
         testScript("joins.sql");
         testScript("range_table.sql");
         testScript("altertable-index-reuse.sql");
+        testScript("altertable-fk.sql");
         testScript("default-and-on_update.sql");
         testScript("query-optimisations.sql");
         String decimal2;

h2/src/test/org/h2/test/scripts/altertable-fk.sql

+-- Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
+-- and the EPL 1.0 (http://h2database.com/html/license.html).
+-- Initial Developer: H2 Group
+--
+
+-- Check that constraints are properly renamed when we rename a column.
+
+CREATE TABLE user_group (ID decimal PRIMARY KEY NOT NULL);
+> ok
+
+CREATE TABLE login_message (ID decimal PRIMARY KEY NOT NULL, user_group_id decimal);
+> ok
+
+ALTER TABLE login_message ADD CONSTRAINT FK_LOGIN_MESSAGE
+FOREIGN KEY (user_group_id)
+REFERENCES user_group(id) ON DELETE CASCADE;
+> ok
+
+ALTER TABLE login_message ALTER COLUMN user_group_id RENAME TO user_group_id2;
+> ok
+
+INSERT INTO user_group (ID) VALUES (1);
+> update count: 1
+
+DELETE FROM user_group;
+> update count: 1
+