Issue 485: Database get corrupted when column is renamed for which check…

Issue 485: Database get corrupted when column is renamed for which check constraint was defined inside create table statement.

h2/src/docsrc/html/changelog.html

@@ -61,6 +61,7 @@ Change Log
 </li><li>Issue 486: MySQL compatibiltity, support the "DEFAULT CHARSET" part of the CREATE TABLE statement.
 </li><li>Issue 487: support the MySQL "SET foreign_key_checks = 0" command
 </li><li>Issue 490: support MySQL "USING BTREE" index declaration
+</li><li>Issue 485: Database get corrupted when column is renamed for which check constraint was defined inside create table statement.
 </li></ul>
 
 <h2>Version 1.3.172 (2013-05-25)</h2>

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

@@ -11,6 +11,7 @@ import org.h2.engine.Database;
 import org.h2.engine.DbObject;
 import org.h2.engine.Right;
 import org.h2.engine.Session;
+import org.h2.expression.Expression;
 import org.h2.table.Column;
 import org.h2.table.Table;
 
@@ -46,7 +47,11 @@ public class AlterTableRenameColumn extends DefineCommand {
         Database db = session.getDatabase();
         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);
         table.renameColumn(column, newName);
+        column.removeCheckConstraint();
+        column.addCheckConstraint(session, newCheckExpr);
         table.setModified();
         db.update(session, table);
         for (DbObject child : table.getChildren()) {

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

@@ -560,6 +560,11 @@ public class Column {
         checkConstraintSQL = getCheckConstraintSQL(session, name);
     }
 
+    public void removeCheckConstraint() {
+        checkConstraint = null;
+        checkConstraintSQL = null;
+    }
+    
     /**
      * Get the check constraint expression for this column if set.
      *

h2/src/test/org/h2/test/db/TestAlter.java

@@ -39,6 +39,7 @@ public class TestAlter extends TestBase {
         stat = conn.createStatement();
         testAlterTableAlterColumnAsSelfColumn();
         testAlterTableDropColumnWithReferences();
+        testAlterTableAlterColumnWithConstraint();
         testAlterTableAlterColumn();
         testAlterTableDropIdentityColumn();
         testAlterTableAddColumnIfNotExists();
@@ -107,6 +108,23 @@ public class TestAlter extends TestBase {
 
     }
 
+    /**
+     * Tests a bug we used to have where altering the name of a column that had a check constraint
+     * that referenced itself would result in not being able to re-open the DB.
+     */
+    private void testAlterTableAlterColumnWithConstraint() throws SQLException {
+        stat.execute("create table test(id int check(id in (1,2)) )");
+        stat.execute("alter table test alter id rename to id2");
+        // disconnect and reconnect
+        conn.close();
+        conn = getConnection("alter");
+        stat = conn.createStatement();
+        stat.execute("insert into test values(1)");
+        assertThrows(ErrorCode.CHECK_CONSTRAINT_VIOLATED_1, stat).
+            execute("insert into test values(3)");
+        stat.execute("drop table test");
+    }
+    
     private void testAlterTableDropIdentityColumn() throws SQLException {
         stat.execute("create table test(id int auto_increment, name varchar)");
         stat.execute("alter table test drop column id");