GOTO PREVIOUS

Branches from an exception handler to the command that caused the exception.

Syntax

GOTO PREVIOUS

Comments

GOTO PREVIOUS is used only in an exception handler and only to branch to the command that caused the exception to occur. GOTO PREVIOUS exits the exception handler, and closes it in the same way as ENDON.

Example

Note: In this example, all transactions are assumed to be implicit transactions (i.e., single commands).

procedure UpdateDB()
 on deadlock
  output "The database is busy."
  output "Do you want to try again? ( y/ n):" ;
  input Response
  if Response = " y"
     goto previous
  else
   return
    endif
   endon
 ... the rest of the commands in the procedure ...
endprocedure

If a deadlock condition occurs, the exception handler asks the application user if the transaction should be attempted again. If the answer is yes, the GOTO PREVIOUS command causes the application program to retry the command that caused the deadlock condition. If the answer is no, the procedure terminates.

 

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