Thanks for the information! It may be worth noting that the issue you bring up can happen as easily with CICS. Or really any situation where more than one person can read/update the same record.
Frank >________________________________ > From: Mike Schwab <[email protected]> >To: [email protected] >Sent: Thursday, February 16, 2012 5:28 PM >Subject: Re: CICS vs IMS > >On Thu, Feb 16, 2012 at 11:44 AM, Frank Swarbrick ><[email protected]> wrote: ><deleted> >> 1) How does BMS compare to MFS. Power, flexibility, ease of use. >Pretty similar. One run to create a binary map, one run to create the >copybook. > >> 2) Does IMS TM have an API for "miscellaneous functions" other than just >> sending and receiving data? Like, does it have (or need) things that >> transient data queues, temp storage queues, etc. >If you have a save area, the call to your program includes the area. >Yes, you can write to a que file for larger data storage. > >> 3) Does IMS TM support VSAM, or just IMS DB and DB2? >I think you have to create a fake IMS DB definition that reads a >native VSAM file. > >> 4) All CICS transactions run inside a single address space (assuming only >> once CICS region, of course). I believe this to not be the case for IMS TM, >> but to be honest I don't really understand how IMS TM works in this regard. >> Is there a "control" region that dispatches "transactions" to run each in >> their own "message processing region"? >> >> 4a) Is the IMS TM (DCCTL?) control region the same region as the IMS DB >> (DBCTL) region, assuming you have a DB/DC configuration? >> >> Frank >You can define a region to contain just databases, or just >transactions, or both. In addition, you can have Batch message >programs that can process a file and update your live database while >online transactions continue. > >One problem I have run into is multiple online updates to one or more >related records. We solved this by putting a timestamp in the record. >When you did an inquiry with a potential to update, you put the >timestamp in MDT hidden fields on the screen. Then when you went to >update, if the time stamp does not match, reject the updated because >database had been updated. Without the timestamp, you could open 2 >TN3270 session on one PC, browse to the same record(s) in both >session, then change the text on both screens. When you press enter >on the first screen, those changes were applied, then the enter on the >other screen would change the records (resulting in overlaid text and >bad keys), after the time stamp it was rejected and the screen was >refreshed with the new database records. >-- >Mike A Schwab, Springfield IL USA >Where do Forest Rangers go to get away from it all? > >---------------------------------------------------------------------- >For IBM-MAIN subscribe / signoff / archive access instructions, >send email to [email protected] with the message: INFO IBM-MAIN > > > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
