IMS Logging

rafaelantunes · New User Joined: 10 May 2007 Posts: 32 Location: Portugal

Ok, so this should be tricky to explain but here it goes...

The short version is: I'm currently implementing a portal that receives data from about 15 different systems. The process that retrieves the data is taking forever (we already tried different approaches but no major bennefits were obtained). So we need to create a local DB that will be refreshed every time that the data is being updated on original system.

The 15 systems are supported by DB2 or IMS. We are currently focused on IMS.

Right now I only need to identified that a record was updated (it does not mather what, only that it was updated).

Is it possible to access the IMS logging and identify the updated records?

If yes, do you know where can I have access to more information?

Any help will be much appreciated.

Regards

charanmsrit · New User Joined: 25 Oct 2007 Posts: 81 Location: Australia

understand that this is few months old now.

It should be possible to identify the updated records using IMS logs because most of the CDC (Change Data Capture) technologies like IBM Infosphere and Informatica works on this principle. I think IBM IMS Diagnosis manuals may help a bit to identify the record type etc from the dump. log
record type X'50' seems to be the one.

You may want to consider CDC technology if your shop already has it??

Nic Clouston · Posted: Thu May 09, 2013 10:53 pm

When we were wanting to update our QMF data sources when our IMS databases were updated we had a module which had the same name as the IMS module but came higher up in the pecking order. It took images of the update to a file before calling the real IMS module. Something along those lines - it was over 20 years ago and I did not have any active participation in it - I was just the application baby-sitter.

Gary Jacek · Posted: Fri May 10, 2013 2:25 am

It would help if we knew what version of IMS is being used.

IMS logs the updates in the 5050 log record.

Old versions of IMS would log the undo/redo (before/after) image of the database segment. More recent IMS versions only log the data that is changed, along with the RBA (location) in the database where the data was updated.

If you are post-processing the IMS logs, Deepak Kohli of IBM has produced a good overview of what you can find in the logs.

There is also a change data capture exit and a few vendors that can assist you to use this to advantage. There is an IMS manual that is specific to customizing IMS exits. You should be able to find the manual that is specific to your IMS version in the InfoCentre.

If you are running a recent IMS (V11 V12) there are also alternatives whereby you can use IMS Connect/TCPIP to plug directly into the IMS data using Java/SQL. So no need to replicate the data.

If you are worried that IMS Connect is too slow, consider that when I last checked, FEDEX ran their entire package delivery/consumer tracking operation through 2 instances of IMS Connect.

Ed Goodman · Active Member Joined: 08 Jun 2011 Posts: 556 Location: USA

Gary, you're a heretic. All applications on the mainframe are much worse than anything being written today. All data MUST reside on the DBMS which had the glossy ad in the most popular trade magazine.

Don't cloud the issue with facts, like the ability of IMS Connect to handle massive loads of work without stumbling.

The contracts have already been signed, the money is already spent, get with the program!

Gary Jacek · Posted: Mon May 13, 2013 9:35 pm

You made me laugh Ed. Let me return the favour.

A decade ago, during an open cabinet meeting, this Liberal cabinet minister demonstrated his mastery of the glossy seatback magazine.

www.youtube.com/watch?v=_asMurMUe7A

Tomorrow the voters in British Columbia go to the polls to elect a new provincial government. There is a good chance that the Liberal party may be tossed out. But the IMS remains.