TRANSACTION
TRANSACTION'BEGIN
TRANSACTION'COMMIT
TRANSACTION'ROLLBACK
These are extensions only available in A-Shell (and which require the COMPIL /X:2 switch). Together they allow you to implement "transactions" (which are logical operations involving multiple physical operations on one or more files which should be done as a logical unit, i.e. either all or nothing).
TRANSACTION'BEGIN marks the beginning of the transaction.
TRANSACTION'COMMIT marks the successful end of the transaction.
TRANSACTION'ROLLBACK aborts the transaction, discarding all changes since the TRANSACTION'BEGIN operation.
Note that while you may operate on any number of files between the TRANSACTION'BEGIN and either the TRANSACTION'COMMIT or TRANSACTION'ROLLBACK, only those ISAM-A files which were opened after the TRANSACTION'LOG'OPEN will be affected by the transaction statements. Any operations to other files will take place normally and immediately, just as they would in the absence of the transaction statements.
See the discussion on Transactions and Logging for more details.
