In an ANSI-compliant database, you do not need BEGIN WORK to mark the beginning of a transaction. You only need to mark the end of each transaction, because a transaction is always in effect. A new transaction starts automatically after each COMMIT WORK or ROLLBACK WORK statement.
You must, however, issue an explicit COMMIT WORK statement to mark the end of each transaction. If you fail to do so, the database server rolls back any modifications that the transaction made to the database.
In an ANSI-compliant database, however, if no error is encountered while you exit from DB–Access in non-interactive mode without issuing the CLOSE DATABASE, COMMIT WORK, or DISCONNECT statement, the database server automatically commits any open transaction.
Related statements: BEGIN WORK, SAVE EXTERNAL DIRECTIVES, and DECLARE
For a discussion of concepts related to transactions, see the IBM Informix Guide to SQL: Tutorial.