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Start( ),BYTE,VIRTUAL

Start is a virtual method used to begin the TransactionManager transaction process. Start makes sure that a transaction is not already running, clears the target RelationManager's internal UseLogout property, manages and issues a LOGOUT for all active tables contained in the target RelationManagers maintained by the TransactionManager.

If the initialization and LOGOUT statement are successful, Start returns a Level:Benign error level. If the Start method is for any reason unsuccessful, a Level:Fatal error level is returned.

Return Value:     BYTE

Implementation:

In a form (update) procedure, the Start method is called just prior to the Window Manager's TakeCompleted method. In a process procedure that implements the TransactionManager, the Start method can be called for each individual method processed, or can be called for a specified number of records processed.

Example:

!In a Form procedure

 IF SELF.Request<;>ViewRecord

  ReturnValue = Transaction.Start()

  IF ReturnValue<;>Level:Benign THEN RETURN ReturnValue.

 END

 ReturnValue = PARENT.TakeCompleted()

 ! A ReturnValue other than Level:Benign will rollback the transaction

 IF SELF.Request<;>ViewRecord

  Transaction.Finish(ReturnValue)

 END

!In a process procedure that individually processes each record

ThisWindow.OpenReport PROCEDURE

ReturnValue          BYTE,AUTO

 CODE

 ReturnValue = PARENT.OpenReport()

 IF ReturnValue = Level:Benign

    ReturnValue = Transaction.Start()

 END

 RETURN ReturnValue

!In a process procedure that processes a batch of records

ThisProcess.TakeRecord PROCEDURE

ReturnValue          BYTE,AUTO

 CODE

 ReturnValue = PARENT.TakeRecord()

 ! —————————————————-

 !

 ! Transaction Check Point

 ! The transaction will be saved till this point

 ! and a new one will be started

 !

 IF SELF.RecordsProcessed % 100 = 0

    Transaction.Finish(ReturnValue)

    IF ReturnValue = Level:Benign

       ReturnValue = Transaction.Start()

    END

 END

 ! —————————————————-

 PUT(Process:View)

 IF ERRORCODE()

   GlobalErrors.ThrowFile(Msg:PutFailed,'Process:View')

   ThisWindow.Response = RequestCompleted

   ReturnValue = Level:Fatal

 END

 RETURN ReturnValue

See Also: Finish