ROLLBACK PREPARED
Name
ROLLBACK PREPARED -- cancel a transaction that was earlier prepared for two-phase commit
Synopsis
ROLLBACK PREPARED transaction_id
Description
   ROLLBACK PREPARED rolls back a transaction that is in
   prepared state.
  
Parameters
- transaction_id
-       The transaction identifier of the transaction that is to be
      rolled back.
      
Notes
   To roll back a prepared transaction, you must be either the same user that
   executed the transaction originally, or a superuser.  But you do not
   have to be in the same session that executed the transaction.
  
   This command cannot be executed inside a transaction block. The prepared
   transaction is rolled back immediately.
  
   All currently available prepared transactions are listed in the
   pg_prepared_xacts
   system view.
  
Examples
   Roll back the transaction identified by the transaction
   identifier foobar:
ROLLBACK PREPARED 'foobar';