DB2 & IMS

The purpose of this issue’s column is to look at the status of the DB2 for z/OS community. I thought it might be useful to examine what versions are available, and what it might mean for DB2 users. Of course, I’ll do all this from the perspective of my opinion only. After all, I don’t work for IBM.

First of all, IBM released DB2 9 for z/OS for general availability on March 16, 2007. I discussed the highlights of the release in the February/March column, so I won’t rehash that here. But even though DB2 9 is now GA, many organizations are still working through their migration to Version 8. Or even worse, many haven’t yet even begun to migrate!

So what about the status of V8? Well, V8 went GA almost three years ago, way back in March 2004. V8 is one of the biggest releases of DB2 for z/OS in the history of DB2. There are more lines of new code in V8 than there were total lines of code in V1 of DB2 back in 1985. So it’s a significant task to formulate a plan for migrating your DB2 subsystems to V8. Of course, if you haven’t already done so, you will be shortly. Why?

The end of marketing for V7, which means it’s no longer sold by IBM, occurred on March 5, 2007. And although DB2 V7 is still serviced and supported by IBM, it will soon be withdrawn from services. In early February 2007, IBM announced that DB2 V7 will go out of service on June 30, 2008. That is a little more than a year away! So, if you haven’t yet developed your migration plan for DB2 V8, now is the time!

OK, then, what is the status of the DB2 community today? Now remember, this is only my opinion, but I’d say that for many shops, DB2 is ahead of them. There are quite a few users struggling to keep up; they don’t use, and even worse, may not understand, all the features and functionality DB2 offers.

Oh, sure, some shops have had V8 in production for years now and are eagerly awaiting the next version. But this class of users is smaller than those struggling to keep up.

The point I’m trying to make here is that if you’re still on V7, you’re behind the curve, and should complete your migration planning for V8 as soon as possible. And plan to be in production with V8 before the end of the year, at the latest.

Keep in mind, though, that some shops, which have only recently migrated to V8, are still somewhat behind the curve. It has taken longer for DB2 shops to embrace V8 than for any previous version of DB2. In the past, it never took almost three years for a new version or release of DB2 to become the primary operational version in the field.

My informal polling indicates that only recently has the production installed base for V8 exceeded 50 percent. I think there are two reasons for this. First, of course, is that IBM significantly re-engineered the “guts” of DB2. As such, users were cautious with their migration plans, and rightly so.

But I think there’s another ancillary cause: the risk vs. reward equation. Although V8 offers numerous benefits in terms of scalability, new features and performance options, it comes at a price. That price is planning to ensure the transition is smooth. You need to worry about things such as the new modes (CM, ENFM, NFM) introduced in V8, the fact that older COBOL compilers are no longer supported, the conversion of your catalog to Unicode, and managing the REBIND process for all your packages and plans. And don’t forget to check on your Coded Character Set Identifiers (CCSIDs) because data corruption can occur if you have multiple CCSIDs within one encoding scheme. But, believe me, this is by no means an exhaustive list of the things you need to address as you migrate from V7 to V8.

The bottom line is that many shops were (and some still are) operating “good enough” on V7, so there was no need to rock the boat by forcing a V8 migration. But now that DB2 9 is GA, and we know when V7 will no longer be supported, the boat is rocking. The time for a 100 percent installed base for V8 is nigh. If you haven’t already done so, you should immediately start developing your DB2 V8 migration plans. Z