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hahy
Front End Web Development Techdegree Student 10,059 PointsROLLBACK before or after switching Autocommit on?
I have one concern. As we see in this video, ROLLBACK is used in a transaction. (BEGIN ... ROLLBACK ... COMMIT). What happen if we create a transaction then ROLLBACK that transaction. Is it possible to undo that transaction? Ex: BEGIN; .... COMMIT; ROLLBACK;
1 Answer
Chris Jones
Java Web Development Techdegree Graduate 23,933 PointsHi hahy,
Once you've committed the transaction, you can't roll it back. Here is some documentation on that from Microsoft's T-SQL.
However, based on the documentation below it sounds like there are some exceptions to that general rule, like a commitment is nested is nested inside a larger transaction and the larger transaction is rolled back.
"A transaction cannot be rolled back after a COMMIT TRANSACTION statement is executed, except when the COMMIT TRANSACTION is associated with a nested transaction that is contained within the transaction being rolled back. In this instance, the nested transaction will also be rolled back, even if you have issued a COMMIT TRANSACTION for it."
https://docs.microsoft.com/en-us/sql/t-sql/language-elements/rollback-transaction-transact-sql
Hope that helps! Let me know if you have any more questions!