BDC

[Former Member]

hi gurus......

What is the use of BDC update type "LOCAL"

[Former Member]

The main update technique for bundling database changes in a single database LUW is to use CALL FUNCTIONu2026 IN UPDATE TASK. This section describes various ways of updating the database.

A program can send an update request using COMMIT WORK.

To the update work process, where it is processed asynchronously. The program does not wait for the work process to finish the update ( Asynchronous Update).

For asynchronous processing in two steps ( Updating Asynchronously in Steps.)

To the update work process, where it is processed synchronously. The program waits for the work process to finish the update ( Synchronous Update).

To its own work process locally. In this case, of course, the program has to wait until the update is finished ( Local Update.)

Local Update

In a local update, the update program is run by the same work process that processed the request. The dialog user has to wait for the update to finish before entering further data. This kind of update is useful when you want to reduce the amount of access to the database. The disadvantage of local updates is their parallel nature. The updates can be processed by many different work processes, unlike asynchronous or synchronous update, where the update is serialized due to the fact that there are fewer update work processes (and maybe only one).

You switch to local update using the ABAP statement SET UPDATE TASK LOCAL. This statement sets a u201Clocal update switchu201D. When it is set, the system interprets CALL FUNCTION IN UPDATE TASK as a request for local update. The update is processed in the same work process as the dialog step containing the COMMIT WORK. The transaction waits for the update to finish before continuing.

As an example, suppose you have a program that uses asynchronous update that you normally run in dialog mode. However, this time you want to run it in the background. Since the system response time is irrelevant when you are running the program in the background, and you only want the program to continue processing when the update has actually finished, you can set the SET UPDATE TASK LOCAL switch in the program. You can then use a system variable to check at runtime whether the program is currently running in the background.

By default, the local update switch is not set, and it is reset after each COMMIT WORK or ROLLBACK WORK. You therefore need to include a SET UPDATE TASK LOCAL statement at the beginning of each SAP LUW.If you reset data within the local update, the ROLLBACK WORK statement applies to both the dialog and the update part of the transaction, since no new SAP LUW is started for the update