ROLLBACK
Name
ROLLBACK -- abort the current transaction
Synopsis
ROLLBACK [ WORK | TRANSACTION ]
Description
ROLLBACK rolls back the current transaction and causes all the updates made by the transaction to be discarded. 
Parameters
- WORK
TRANSACTION  Optional key words. They have no effect. 
Notes
 Use COMMIT to successfully terminate a transaction. 
 Issuing ROLLBACK outside of a transaction block emits a warning and otherwise has no effect. 
Examples
 To abort all changes: 
ROLLBACK;
Compatibility
 The SQL standard only specifies the two forms ROLLBACK and ROLLBACK WORK. Otherwise, this command is fully conforming.