How to rollback a database transaction

Hi guys, I’m trying to use database activity. I want to know how to rollback a database transaction. I have tried to use the start transaction with the UseTransaction property checked, and within it, I drag two Execute non query activity, the first one update a column value in a table, the second one rollback. But when I run, I got this error: Execute non query : You tried to commit or rollback a transaction without first beginning a transaction. And the result in hadn’t been change at all. Anyone can help me? Why this error would appear? Can’t Start Transaction activity begin a transaction?