Un serialized V3 ....

Question

Hi all,
I understand the V3 job as follows:
when user enters the tranxn, it will be written to application tables in V1 and written to update tables in V2, when ever we schedule a V3 job, it transfers data from update tables to delta queue.
based on above, Unserialized V3 is dependent of V2 job?
Update tables are updated in V2 job?
Am I correct..

Answer 1

Update methods: Un-serialized V3
• Extraction data for written as before into the update tables with a V3 update module
• V3 collective run transfers the data to BW Delta queue
• In contrast to serialized V3, the data in the updating collective run is without regard to sequence from the update tables
Transaction postings lead to:
1. Records in transaction tables and in update tables
2. A periodically scheduled job transfers these postings into the BW delta queue
3.This BW Delta queue is read when a delta load is executed.
Issues:
• Only suitable for data target design for which correct sequence of changes is not important e.g. Material Movements
• V2 update has to be successful
Direct Delta: With this update mode, the extraction data is transferred with each document posting directly into the BW delta queue. In doing so, each document posting with delta extraction is posted for exactly one LUW in the respective BW delta queues.
Queued Delta: With this update mode, the extraction data is collected for the affected application instead of being collected in an extraction queue, and can be transferred as usual with the V3 update by means of an updating collective run into the BW delta queue. In doing so, up to 10000 delta extractions of documents for an LUW are compressed for each DataSource into the BW delta queue, depending on the application.
Non-serialized V3 Update:With this update mode, the extraction data for the application considered is written as before into the update tables with the help of a V3 update module. They are kept there as long as the data is selected through an updating collective run and are processed. However, in contrast to the current default settings (serialized V3 update), the data in the updating collective run are thereby read without regard to sequence from the update tables and are transferred to the BW delta queue.
V1 - Synchronous update
V2 - Asynchronous update
V3 - Batch asynchronous update
These are different work processes on the application server that takes the update LUW (which may have various DB manipulation SQLs) from the running program and execute it. These are separated to optimize transaction processing capabilities.
Taking an example -
If you create/change a purchase order (me21n/me22n), when you press 'SAVE' and see a success message (PO.... changed..), the update to underlying tables EKKO/EKPO has happened (before you saw the message). This update was executed in the V1 work process.
There are some statistics collecting tables in the system which can capture data for reporting. For example, LIS table S012 stores purchasing data (it is the same data as EKKO/EKPO stored redundantly, but in a different structure to optimize reporting). Now, these tables are updated with the txn you just posted, in a V2 process. Depending on system load, this may happen a few seconds later (after you saw the success message). You can see V1/V2/V3 queues in SM12 or SM13.
V3 is specifically for BW extraction. The update LUW for these is sent to V3 but is not executed immediately. You have to schedule a job (eg in LBWE definitions) to process these. This is again to optimize performance.
V2 and V3 are separated from V1 as these are not as realtime critical (updating statistical data). If all these updates were put together in one LUW, system performance (concurrency, locking etc) would be impacted.
Hope it will helps you.......