A series of changes made to a recordset.  You mark the beginning of a transaction with the BeginTrans statement.  To commit the transaction, use the CommitTrans statement.  To undo all your changes since BeginTrans, use the Rollback statement.

There is an implicit transaction while queries are running.  If a query does not complete for any reason, it is automatically rolled back.

Transactions are optional and can be nested up to five levels.