Fixed CR/LF issue with Git

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

-/*
- * Copyright 2004-2014 H2 Group. Multiple-Licensed under the MPL 2.0,
- * and the EPL 1.0 (http://h2database.com/html/license.html).
- * Initial Developer: H2 Group
- */
-package org.h2.test.db;
-
-import java.sql.Connection;
-import java.sql.DatabaseMetaData;
-import java.sql.ResultSet;
-import java.sql.SQLException;
-import java.sql.Statement;
-import org.h2.api.ErrorCode;
-import org.h2.test.TestBase;
-
-/**
- * Test ALTER statements.
- */
-public class TestAlter extends TestBase {
-
-    private Connection conn;
-    private Statement stat;
-
-    /**
-     * Run just this test.
-     *
-     * @param a ignored
-     */
-    public static void main(String... a) throws Exception {
-        TestBase.createCaller().init().test();
-    }
-
-    @Override
-    public void test() throws Exception {
-        deleteDb(getTestName());
-        conn = getConnection(getTestName());
-        stat = conn.createStatement();
-        testAlterTableRenameConstraint();
-        testAlterTableAlterColumnAsSelfColumn();
-        testAlterTableDropColumnWithReferences();
-        testAlterTableDropMultipleColumns();
-        testAlterTableAlterColumnWithConstraint();
-        testAlterTableAlterColumn();
-        testAlterTableAddColumnIdentity();
-        testAlterTableDropIdentityColumn();
-        testAlterTableAddColumnIfNotExists();
-        testAlterTableAddMultipleColumns();
-        testAlterTableAlterColumn2();
-        testAlterTableAddColumnBefore();
-        testAlterTableAddColumnAfter();
-        testAlterTableAddMultipleColumnsBefore();
-        testAlterTableAddMultipleColumnsAfter();
-        testAlterTableModifyColumn();
-        testAlterTableModifyColumnSetNull();
-        conn.close();
-        deleteDb(getTestName());
-    }
-
-    private void testAlterTableAlterColumnAsSelfColumn() throws SQLException {
-        stat.execute("create table test(id int, name varchar)");
-        stat.execute("alter table test alter column id int as id+1");
-        stat.execute("insert into test values(1, 'Hello')");
-        stat.execute("update test set name='World'");
-        ResultSet rs = stat.executeQuery("select * from test");
-        rs.next();
-        assertEquals(3, rs.getInt(1));
-        stat.execute("drop table test");
-    }
-
-    private void testAlterTableDropColumnWithReferences() throws SQLException {
-        stat.execute("create table parent(id int, b int)");
-        stat.execute("create table child(p int primary key)");
-        stat.execute("alter table child add foreign key(p) references parent(id)");
-        stat.execute("alter table parent drop column id");
-        stat.execute("drop table parent");
-        stat.execute("drop table child");
-
-        stat.execute("create table test(id int, name varchar(255))");
-        stat.execute("alter table test add constraint x check (id > name)");
-
-        // the constraint references multiple columns
-        assertThrows(ErrorCode.COLUMN_IS_REFERENCED_1, stat).
-                execute("alter table test drop column id");
-
-        stat.execute("drop table test");
-
-        stat.execute("create table test(id int, name varchar(255))");
-        stat.execute("alter table test add constraint x unique(id, name)");
-
-        // the constraint references multiple columns
-        assertThrows(ErrorCode.COLUMN_IS_REFERENCED_1, stat).
-                execute("alter table test drop column id");
-
-        stat.execute("drop table test");
-
-        stat.execute("create table test(id int, name varchar(255))");
-        stat.execute("alter table test add constraint x check (id > 1)");
-        stat.execute("alter table test drop column id");
-        stat.execute("drop table test");
-
-        stat.execute("create table test(id int, name varchar(255))");
-        stat.execute("alter table test add constraint x check (name > 'TEST.ID')");
-        // previous versions of H2 used sql.indexOf(columnName)
-        // to check if the column is referenced
-        stat.execute("alter table test drop column id");
-        stat.execute("drop table test");
-
-        stat.execute("create table test(id int, name varchar(255))");
-        stat.execute("alter table test add constraint x unique(id)");
-        stat.execute("alter table test drop column id");
-        stat.execute("drop table test");
-
-    }
-
-    private void testAlterTableDropMultipleColumns() throws SQLException {
-        stat.execute("create table test(id int, name varchar, name2 varchar)");
-        stat.execute("alter table test drop column name, name2");
-        stat.execute("drop table test");
-        // Test-Case: Same as above but using brackets (Oracle style)
-        stat.execute("create table test(id int, b varchar, c int, d int)");
-        stat.execute("alter table test drop column (b, c)");
-        assertThrows(ErrorCode.COLUMN_NOT_FOUND_1, stat).
-            execute("alter table test drop column b");
-        stat.execute("alter table test drop (d)");
-        stat.execute("drop table test");
-        // Test-Case: Error if dropping all columns 
-        stat.execute("create table test(id int, name varchar, name2 varchar)");
-        assertThrows(ErrorCode.CANNOT_DROP_LAST_COLUMN, stat).
-            execute("alter table test drop column id, name, name2");
-        stat.execute("drop table test");
-    }
-
-    /**
-     * 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 {
-        if (config.memory) {
-            return;
-        }
-        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(getTestName());
-        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 testAlterTableRenameConstraint() throws SQLException {
-        stat.execute("create table test(id int, name varchar(255))");
-        stat.execute("alter table test add constraint x check (id > name)");
-        stat.execute("alter table test rename constraint x to x2");
-        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");
-        ResultSet rs = stat.executeQuery("select * from INFORMATION_SCHEMA.SEQUENCES");
-        assertFalse(rs.next());
-        stat.execute("drop table test");
-
-        stat.execute("create table test(id int auto_increment, name varchar)");
-        stat.execute("alter table test drop column name");
-        rs = stat.executeQuery("select * from INFORMATION_SCHEMA.SEQUENCES");
-        assertTrue(rs.next());
-        stat.execute("drop table test");
-    }
-
-    private void testAlterTableAlterColumn() throws SQLException {
-        stat.execute("create table t(x varchar) as select 'x'");
-        assertThrows(ErrorCode.DATA_CONVERSION_ERROR_1, stat).
-                execute("alter table t alter column x int");
-        stat.execute("drop table t");
-        stat.execute("create table t(id identity, x varchar) as select null, 'x'");
-        assertThrows(ErrorCode.DATA_CONVERSION_ERROR_1, stat).
-                execute("alter table t alter column x int");
-        stat.execute("drop table t");
-    }
-
-    private void testAlterTableAddColumnIdentity() throws SQLException {
-        stat.execute("create table t(x varchar)");
-        stat.execute("alter table t add id bigint identity(5, 5) not null");
-        stat.execute("insert into t values (null, null)");
-        stat.execute("insert into t values (null, null)");
-        ResultSet rs = stat.executeQuery("select id from t order by id");
-        assertTrue(rs.next());
-        assertEquals(5, rs.getInt(1));
-        assertTrue(rs.next());
-        assertEquals(10, rs.getInt(1));
-        assertFalse(rs.next());
-        stat.execute("drop table t");
-    }
-
-    private void testAlterTableAddColumnIfNotExists() throws SQLException {
-        stat.execute("create table t(x varchar) as select 'x'");
-        stat.execute("alter table t add if not exists x int");
-        stat.execute("drop table t");
-        stat.execute("create table t(x varchar) as select 'x'");
-        stat.execute("alter table t add if not exists y int");
-        stat.execute("select x, y from t");
-        stat.execute("drop table t");
-    }
-
-    private void testAlterTableAddMultipleColumns() throws SQLException {
-        stat.execute("create table t(x varchar) as select 'x'");
-        stat.execute("alter table t add (y int, z varchar)");
-        stat.execute("drop table t");
-        stat.execute("create table t(x varchar) as select 'x'");
-        stat.execute("alter table t add (y int)");
-        stat.execute("drop table t");
-    }
-
-
-    
-    // column and field names must be upper-case due to getMetaData sensitivity
-    private void testAlterTableAddMultipleColumnsBefore() throws SQLException {
-        stat.execute("create table T(X varchar)");
-        stat.execute("alter table T add (Y int, Z int) before X");
-        DatabaseMetaData dbMeta = conn.getMetaData();
-        ResultSet rs = dbMeta.getColumns(null, null, "T", null);
-        assertTrue(rs.next());
-        assertEquals("Y", rs.getString("COLUMN_NAME"));
-        assertTrue(rs.next());
-        assertEquals("Z", rs.getString("COLUMN_NAME"));
-        assertTrue(rs.next());
-        assertEquals("X", rs.getString("COLUMN_NAME"));
-        assertFalse(rs.next());
-        stat.execute("drop table T");
-    }
-
-    // column and field names must be upper-case due to getMetaData sensitivity
-    private void testAlterTableAddMultipleColumnsAfter() throws SQLException {
-        stat.execute("create table T(X varchar)");
-        stat.execute("alter table T add (Y int, Z int) after X");
-        DatabaseMetaData dbMeta = conn.getMetaData();
-        ResultSet rs = dbMeta.getColumns(null, null, "T", null);
-        assertTrue(rs.next());
-        assertEquals("X", rs.getString("COLUMN_NAME"));
-        assertTrue(rs.next());
-        assertEquals("Y", rs.getString("COLUMN_NAME"));
-        assertTrue(rs.next());
-        assertEquals("Z", rs.getString("COLUMN_NAME"));
-        assertFalse(rs.next());
-        stat.execute("drop table T");
-    }
-
-    // column and field names must be upper-case due to getMetaData sensitivity
-    private void testAlterTableAddColumnBefore() throws SQLException {
-        stat.execute("create table T(X varchar)");
-        stat.execute("alter table T add Y int before X");
-        DatabaseMetaData dbMeta = conn.getMetaData();
-        ResultSet rs = dbMeta.getColumns(null, null, "T", null);
-        assertTrue(rs.next());
-        assertEquals("Y", rs.getString("COLUMN_NAME"));
-        assertTrue(rs.next());
-        assertEquals("X", rs.getString("COLUMN_NAME"));
-        assertFalse(rs.next());
-        stat.execute("drop table T");
-    }
-
-    // column and field names must be upper-case due to getMetaData sensitivity
-    private void testAlterTableAddColumnAfter() throws SQLException {
-        stat.execute("create table T(X varchar)");
-        stat.execute("alter table T add Y int after X");
-        DatabaseMetaData dbMeta = conn.getMetaData();
-        ResultSet rs = dbMeta.getColumns(null, null, "T", null);
-        assertTrue(rs.next());
-        assertEquals("X", rs.getString("COLUMN_NAME"));
-        assertTrue(rs.next());
-        assertEquals("Y", rs.getString("COLUMN_NAME"));
-        assertFalse(rs.next());
-        stat.execute("drop table T");
-    }
-
-    private void testAlterTableAlterColumn2() throws SQLException {
-        // ensure that increasing a VARCHAR columns length takes effect because
-        // we optimize this case
-        stat.execute("create table t(x varchar(2)) as select 'x'");
-        stat.execute("alter table t alter column x varchar(20)");
-        stat.execute("insert into t values('Hello')");
-        stat.execute("drop table t");
-    }
-
-    private void testAlterTableModifyColumn() throws SQLException {
-        stat.execute("create table t(x int)");
-        stat.execute("alter table t modify column x varchar(20)");
-        stat.execute("insert into t values('Hello')");
-        stat.execute("drop table t");
-    }
-    
-    /**
-     * Test for fix "Change not-null / null -constraint to existing column" 
-     * (MySql/ORACLE - SQL style) that failed silently corrupting the changed 
-     * column.<br/>
-     * Before the change (added after v1.4.196) following was observed:
-     * <pre>
-     *  alter table T modify C int null; -- Worked as expected
-     *  alter table T modify C null;     -- Silently corrupted column C
-     * </pre>
-     */
-    private void testAlterTableModifyColumnSetNull() throws SQLException {
-        // This worked in v1.4.196
-        stat.execute("create table T (C varchar not null)");
-        stat.execute("alter table T modify C int null");
-        stat.execute("insert into T values(null)");
-        stat.execute("drop table T");
-        // This failed in v1.4.196 
-        stat.execute("create table T (C int not null)");
-        stat.execute("alter table T modify C null"); // Silently corrupted column C
-        stat.execute("insert into T values(null)"); // <- Fixed in v1.4.196 - NULL is allowed
-        stat.execute("drop table T");
-    }
-}
+/*
+ * Copyright 2004-2014 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.test.db;
+
+import java.sql.Connection;
+import java.sql.DatabaseMetaData;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import org.h2.api.ErrorCode;
+import org.h2.test.TestBase;
+
+/**
+ * Test ALTER statements.
+ */
+public class TestAlter extends TestBase {
+
+    private Connection conn;
+    private Statement stat;
+
+    /**
+     * Run just this test.
+     *
+     * @param a ignored
+     */
+    public static void main(String... a) throws Exception {
+        TestBase.createCaller().init().test();
+    }
+
+    @Override
+    public void test() throws Exception {
+        deleteDb(getTestName());
+        conn = getConnection(getTestName());
+        stat = conn.createStatement();
+        testAlterTableRenameConstraint();
+        testAlterTableAlterColumnAsSelfColumn();
+        testAlterTableDropColumnWithReferences();
+        testAlterTableDropMultipleColumns();
+        testAlterTableAlterColumnWithConstraint();
+        testAlterTableAlterColumn();
+        testAlterTableAddColumnIdentity();
+        testAlterTableDropIdentityColumn();
+        testAlterTableAddColumnIfNotExists();
+        testAlterTableAddMultipleColumns();
+        testAlterTableAlterColumn2();
+        testAlterTableAddColumnBefore();
+        testAlterTableAddColumnAfter();
+        testAlterTableAddMultipleColumnsBefore();
+        testAlterTableAddMultipleColumnsAfter();
+        testAlterTableModifyColumn();
+        testAlterTableModifyColumnSetNull();
+        conn.close();
+        deleteDb(getTestName());
+    }
+
+    private void testAlterTableAlterColumnAsSelfColumn() throws SQLException {
+        stat.execute("create table test(id int, name varchar)");
+        stat.execute("alter table test alter column id int as id+1");
+        stat.execute("insert into test values(1, 'Hello')");
+        stat.execute("update test set name='World'");
+        ResultSet rs = stat.executeQuery("select * from test");
+        rs.next();
+        assertEquals(3, rs.getInt(1));
+        stat.execute("drop table test");
+    }
+
+    private void testAlterTableDropColumnWithReferences() throws SQLException {
+        stat.execute("create table parent(id int, b int)");
+        stat.execute("create table child(p int primary key)");
+        stat.execute("alter table child add foreign key(p) references parent(id)");
+        stat.execute("alter table parent drop column id");
+        stat.execute("drop table parent");
+        stat.execute("drop table child");
+
+        stat.execute("create table test(id int, name varchar(255))");
+        stat.execute("alter table test add constraint x check (id > name)");
+
+        // the constraint references multiple columns
+        assertThrows(ErrorCode.COLUMN_IS_REFERENCED_1, stat).
+                execute("alter table test drop column id");
+
+        stat.execute("drop table test");
+
+        stat.execute("create table test(id int, name varchar(255))");
+        stat.execute("alter table test add constraint x unique(id, name)");
+
+        // the constraint references multiple columns
+        assertThrows(ErrorCode.COLUMN_IS_REFERENCED_1, stat).
+                execute("alter table test drop column id");
+
+        stat.execute("drop table test");
+
+        stat.execute("create table test(id int, name varchar(255))");
+        stat.execute("alter table test add constraint x check (id > 1)");
+        stat.execute("alter table test drop column id");
+        stat.execute("drop table test");
+
+        stat.execute("create table test(id int, name varchar(255))");
+        stat.execute("alter table test add constraint x check (name > 'TEST.ID')");
+        // previous versions of H2 used sql.indexOf(columnName)
+        // to check if the column is referenced
+        stat.execute("alter table test drop column id");
+        stat.execute("drop table test");
+
+        stat.execute("create table test(id int, name varchar(255))");
+        stat.execute("alter table test add constraint x unique(id)");
+        stat.execute("alter table test drop column id");
+        stat.execute("drop table test");
+
+    }
+
+    private void testAlterTableDropMultipleColumns() throws SQLException {
+        stat.execute("create table test(id int, b varchar, c int, d int)");
+        stat.execute("alter table test drop column b, c");
+        stat.execute("alter table test drop d");
+        stat.execute("drop table test");
+        // Test-Case: Same as above but using brackets (Oracle style)
+        stat.execute("create table test(id int, b varchar, c int, d int)");
+        stat.execute("alter table test drop column (b, c)");
+        assertThrows(ErrorCode.COLUMN_NOT_FOUND_1, stat).
+            execute("alter table test drop column b");
+        stat.execute("alter table test drop (d)");
+        stat.execute("drop table test");
+        // Test-Case: Error if dropping all columns 
+        stat.execute("create table test(id int, name varchar, name2 varchar)");
+        assertThrows(ErrorCode.CANNOT_DROP_LAST_COLUMN, stat).
+            execute("alter table test drop column id, name, name2");
+        stat.execute("drop table test");
+    }
+
+    /**
+     * 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 {
+        if (config.memory) {
+            return;
+        }
+        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(getTestName());
+        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 testAlterTableRenameConstraint() throws SQLException {
+        stat.execute("create table test(id int, name varchar(255))");
+        stat.execute("alter table test add constraint x check (id > name)");
+        stat.execute("alter table test rename constraint x to x2");
+        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");
+        ResultSet rs = stat.executeQuery("select * from INFORMATION_SCHEMA.SEQUENCES");
+        assertFalse(rs.next());
+        stat.execute("drop table test");
+
+        stat.execute("create table test(id int auto_increment, name varchar)");
+        stat.execute("alter table test drop column name");
+        rs = stat.executeQuery("select * from INFORMATION_SCHEMA.SEQUENCES");
+        assertTrue(rs.next());
+        stat.execute("drop table test");
+    }
+
+    private void testAlterTableAlterColumn() throws SQLException {
+        stat.execute("create table t(x varchar) as select 'x'");
+        assertThrows(ErrorCode.DATA_CONVERSION_ERROR_1, stat).
+                execute("alter table t alter column x int");
+        stat.execute("drop table t");
+        stat.execute("create table t(id identity, x varchar) as select null, 'x'");
+        assertThrows(ErrorCode.DATA_CONVERSION_ERROR_1, stat).
+                execute("alter table t alter column x int");
+        stat.execute("drop table t");
+    }
+
+    private void testAlterTableAddColumnIdentity() throws SQLException {
+        stat.execute("create table t(x varchar)");
+        stat.execute("alter table t add id bigint identity(5, 5) not null");
+        stat.execute("insert into t values (null, null)");
+        stat.execute("insert into t values (null, null)");
+        ResultSet rs = stat.executeQuery("select id from t order by id");
+        assertTrue(rs.next());
+        assertEquals(5, rs.getInt(1));
+        assertTrue(rs.next());
+        assertEquals(10, rs.getInt(1));
+        assertFalse(rs.next());
+        stat.execute("drop table t");
+    }
+
+    private void testAlterTableAddColumnIfNotExists() throws SQLException {
+        stat.execute("create table t(x varchar) as select 'x'");
+        stat.execute("alter table t add if not exists x int");
+        stat.execute("drop table t");
+        stat.execute("create table t(x varchar) as select 'x'");
+        stat.execute("alter table t add if not exists y int");
+        stat.execute("select x, y from t");
+        stat.execute("drop table t");
+    }
+
+    private void testAlterTableAddMultipleColumns() throws SQLException {
+        stat.execute("create table t(x varchar) as select 'x'");
+        stat.execute("alter table t add (y int, z varchar)");
+        stat.execute("drop table t");
+        stat.execute("create table t(x varchar) as select 'x'");
+        stat.execute("alter table t add (y int)");
+        stat.execute("drop table t");
+    }
+
+
+    
+    // column and field names must be upper-case due to getMetaData sensitivity
+    private void testAlterTableAddMultipleColumnsBefore() throws SQLException {
+        stat.execute("create table T(X varchar)");
+        stat.execute("alter table T add (Y int, Z int) before X");
+        DatabaseMetaData dbMeta = conn.getMetaData();
+        ResultSet rs = dbMeta.getColumns(null, null, "T", null);
+        assertTrue(rs.next());
+        assertEquals("Y", rs.getString("COLUMN_NAME"));
+        assertTrue(rs.next());
+        assertEquals("Z", rs.getString("COLUMN_NAME"));
+        assertTrue(rs.next());
+        assertEquals("X", rs.getString("COLUMN_NAME"));
+        assertFalse(rs.next());
+        stat.execute("drop table T");
+    }
+
+    // column and field names must be upper-case due to getMetaData sensitivity
+    private void testAlterTableAddMultipleColumnsAfter() throws SQLException {
+        stat.execute("create table T(X varchar)");
+        stat.execute("alter table T add (Y int, Z int) after X");
+        DatabaseMetaData dbMeta = conn.getMetaData();
+        ResultSet rs = dbMeta.getColumns(null, null, "T", null);
+        assertTrue(rs.next());
+        assertEquals("X", rs.getString("COLUMN_NAME"));
+        assertTrue(rs.next());
+        assertEquals("Y", rs.getString("COLUMN_NAME"));
+        assertTrue(rs.next());
+        assertEquals("Z", rs.getString("COLUMN_NAME"));
+        assertFalse(rs.next());
+        stat.execute("drop table T");
+    }
+
+    // column and field names must be upper-case due to getMetaData sensitivity
+    private void testAlterTableAddColumnBefore() throws SQLException {
+        stat.execute("create table T(X varchar)");
+        stat.execute("alter table T add Y int before X");
+        DatabaseMetaData dbMeta = conn.getMetaData();
+        ResultSet rs = dbMeta.getColumns(null, null, "T", null);
+        assertTrue(rs.next());
+        assertEquals("Y", rs.getString("COLUMN_NAME"));
+        assertTrue(rs.next());
+        assertEquals("X", rs.getString("COLUMN_NAME"));
+        assertFalse(rs.next());
+        stat.execute("drop table T");
+    }
+
+    // column and field names must be upper-case due to getMetaData sensitivity
+    private void testAlterTableAddColumnAfter() throws SQLException {
+        stat.execute("create table T(X varchar)");
+        stat.execute("alter table T add Y int after X");
+        DatabaseMetaData dbMeta = conn.getMetaData();
+        ResultSet rs = dbMeta.getColumns(null, null, "T", null);
+        assertTrue(rs.next());
+        assertEquals("X", rs.getString("COLUMN_NAME"));
+        assertTrue(rs.next());
+        assertEquals("Y", rs.getString("COLUMN_NAME"));
+        assertFalse(rs.next());
+        stat.execute("drop table T");
+    }
+
+    private void testAlterTableAlterColumn2() throws SQLException {
+        // ensure that increasing a VARCHAR columns length takes effect because
+        // we optimize this case
+        stat.execute("create table t(x varchar(2)) as select 'x'");
+        stat.execute("alter table t alter column x varchar(20)");
+        stat.execute("insert into t values('Hello')");
+        stat.execute("drop table t");
+    }
+
+    private void testAlterTableModifyColumn() throws SQLException {
+        stat.execute("create table t(x int)");
+        stat.execute("alter table t modify column x varchar(20)");
+        stat.execute("insert into t values('Hello')");
+        stat.execute("drop table t");
+    }
+    
+    /**
+     * Test for fix "Change not-null / null -constraint to existing column" 
+     * (MySql/ORACLE - SQL style) that failed silently corrupting the changed 
+     * column.<br/>
+     * Before the change (added after v1.4.196) following was observed:
+     * <pre>
+     *  alter table T modify C int null; -- Worked as expected
+     *  alter table T modify C null;     -- Silently corrupted column C
+     * </pre>
+     */
+    private void testAlterTableModifyColumnSetNull() throws SQLException {
+        // This worked in v1.4.196
+        stat.execute("create table T (C varchar not null)");
+        stat.execute("alter table T modify C int null");
+        stat.execute("insert into T values(null)");
+        stat.execute("drop table T");
+        // This failed in v1.4.196 
+        stat.execute("create table T (C int not null)");
+        stat.execute("alter table T modify C null"); // Silently corrupted column C
+        stat.execute("insert into T values(null)"); // <- Fixed in v1.4.196 - NULL is allowed
+        stat.execute("drop table T");
+    }
+}