Why am I being prompted to commit or rollback when closing the Editor after running a SELECT stat (54195)

After running a SELECT statement in Toad's editor, I am prompted to commit or rollback when I exit the session. Why am I being prompted when all I did was run a select statement?

1. Running an explain plan in Toad.
2. Running a SELECT statement which uses a DBLink.

WORKAROUND:

If the above scenarios in the cause section do not apply, turn off the Toad option to create a separate Toad connection:
1. Go to View | Toad Options from the main menu.
2. On the left go to Oracle - Transactions section.
3. Uncheck the option to "Use a seperate connection when Toad itself is generating a transaction".

This option was removed in version 11.0. You can try unchecking the "Execute query in threads" option, which is on the same options page, and see it that stops the prompt.

When you select through a DB Link, Oracle considers that to be the start of the transaction. So, when you end your session in Toad, Toad asks Oracle “are there any transactions”. If you’ve done a select through a DB Link, Oracle says “yes”, so Toad asks if you want to commit or rollback.

You can read this if you are interested in why Oracle behaves this way.
http://www.jlcomp.demon.co.uk/faq/dblink_commit.html