Assuming Autocommit is set to false:
In case 1
As soon as you execute a DDL statement, before anything happens, a commit is implicitly called by the database ( this also happens when you are working in a SQL session ). No matter what you have set autocommit to, the commit takes place just before the DDL is executed.
In case 2
It can be driver specific/database specific, but in general if the driver supports transactions, then the DML statements will not be committed and the transaction will be rolled back. Try a
test case to verify it or read through your jdbc driver documentation.
Assuming Autocommit is set to true:
after each executeUpdate() a commit takes place
As stated above, the default for autocommit() varies from driver to driver.
Jamie
[ August 30, 2002: Message edited by: Jamie Robertson ]