Do I need to call rollback if I never commit?

Question

I am connecting to a SQL Server using no autocommit. If everything is successful, I call commit. Otherwise, I just exit. Do I need to explicitly call rollback, or will it be rolled back automatically when we close the connection without committing? In case it matters, I'm executing the SQL commands from within proc sql in SAS. **UPDATE:** It looks like SAS may call commit automatically at the end of the proc sql block if rollback is not called. So in this case, rollback would be more than good practice; it would be necessary. **Final Update:** We ended up switching to a new system, which seems to me to behave the opposite of our previous one. On ending the transaction without specifying committing or rolling back, it will roll back. So, the advice given below is definitely correct: always explicitly commit or rollback.

Answer 1

The best practice is to use ROLLBACK even if you never commit. Presumably, you've begun a transaction and that transaction will remain open unless you COMMIT it or roll it back.