MVSFORUMS.com

pacholopezr

Good morning. I have this project, where I need to get some records from some VSAM datasets.

My problem es that those datasets could be really cumbersome, so, I am figuring out a way to extract only the records that have been updated, inserted o deleted.

I have been reading, and using the key or the RBA could be a way to do this. Any other suggestion is more than welcome.

On the other hand. What about getting those changes real time ? Is it possible without have to be intrusive ? I mean, without having to capture SVCs or things like that.

I really appreciate your help.

Francisco

kolusu · Posted: Tue Jun 08, 2004 11:03 am Post subject:

Francisco,

What kind of vsam file are we talking? Records can be deleted from KSDS and RRDS. You cannot delete records from ESDS and LDS. You can update the records in ESDS,KSDS,RRDS but with certain limitations.

I don't think RBA will be useful in this case unless it is an ESDS or RRDS. The RBA can change in KSDS.

The simplest way I can think of is add another VSAM File as Log file. So when ever you perform any operation(ADD/DELETE/UPDATE) on the target file , you will simply write into the LOG vsam File with approriate action code (A - ADD, D - Delete U - Update). This Log file can be can be an ESDS.

At the end of the day you can copy the contents of this LOG file into a GDG and empty out the logfile for the next day transactions.

Hope this helps...

Cheers

Kolusu
_________________
Kolusu
www.linkedin.com/in/kolusu

pacholopezr · Posted: Tue Jun 08, 2004 4:35 pm Post subject:

Sounds great Kolusu, I am going to give it a try to see how it works.

One final thing. This log file basically is going to contain all the full records modified?deleted, etc Very Happy

?
_________________
Francisco Lopez

kolusu · Posted: Wed Jun 09, 2004 5:31 am Post subject:

pacholopezr,

Yes you are right , the log file will contain all the records which are added/updated/deleted from your main file along with an Indicator flag of action.

Kolusu
_________________
Kolusu
www.linkedin.com/in/kolusu

bablack · Posted: Tue Jun 22, 2004 2:37 pm Post subject:

VSAM supports a journal exit. You could write such an exit and assign it to this cluster. All updates will be passed to the journal exit where you can record them somewhere else for later processing.
_________________
Bruce A. Black
Senior Software Developer
Innovation Data Processing