DERBY-4244

I apply the patch(you can find it in JIRA) which is modify by Bryan (java/engine/org/apache/derby/impl/sql/compile/AlterTableNode.java) to the trunk. After applying the patch I saw there are some of the initialized table are not there. I paste the "st.executeUpdate("create table t0_1(c1 int)");" in the near above the alter table t0_1; But the problem was when rollback() command applied the table vanishes out and the further coding cannot see a table named t0_1; I used it in the top of the method, and I got the error message as,

• testAddColumn(org.apache.derbyTesting.functionTests.tests.lang.AlterTableTest) java.sql.SQLException: Table/View 'T0_1' already exists in Schema 'TEST_DBO'.

It shows that the schema must change to default.