Recently, a Search390.com user recently asked Craig Mullins, our DB2 and database management expert, whether he should upgrade to DB2 V8 now. Craig's reply is below.
Whether or not to upgrade to V8 of DB2 for z/OS now requires thought and planning. One of the biggest impacts of V8 will be the requirement to be running a zSeries machine and z/OS v1.3 -- or greater. DB2 V8 will not support old hardware nor will it support OS/390.
Keep in mind, too, that the z/OS v1.3 requirement is the minimum requirement, and you will need v1.4 or v1.5 in order to use certain new DB2 V8 functionality (e.g. MLS).
DB2 customers must migrate to V7 before converting to V8. There will be no IBM-supported capability to jump from V6 (or an older version) directly to V8 without first migrating to V7.
Additionally, you will need to understand the modes of DB2 V8. There are three distinct DB2 operating modes that dictate the functionality available to DB2 when operating in that mode. The modes are:
- Compatibility mode (CM)
- Enabling new function mode (ENFM)
- New functionality mode (NFM)
You will need to read the documentation to understand what new features are available in each of these modes and how to transition through the modes.
Basically, CM is V8 without the new features (except the ability to exploit large virtual storage), ENFM is the interim mode used to convert the system catalog tables to support the new functionality, and NFM is full-blown DB2 V8.
So, my advice is that if you have not yet begun to plan how and when you will upgrade to V8, now is a good time to start planning. On the other hand, if you have already read the transition guide, understand the new functionality and put together a plan, then you are ahead of most folks.