My previous posts about fix packs (here, here and here) and Cumulative Client Hotfixes (CCH) (here) cause a few dedicated blog readers and STS customers to ask what the differences were and which were best for them.

Well there is a nice IBM Technote that describes the differences. Let me see if I can distill this some.....

An MR will essentially upgrade the last digit of the software (8.0.2 is basically 8.0, MR 2). So, MR's contain lots of fixes and maybe functional enhancements too. A fix pack will address any bugs in a MR (or base, x.0 release) and a CCH is a rolling install of hotfixes for a given MR or FP. Confused yet?

Simply put, you want the highest MR you can get, together with the highest FP for that specific MR, together with the highest CCH for that MR + FP combination. Now there are exceptions. There maybe fixes in a CCH that are not yet in the MR and vice versa but as a general rule a CCH will have more recent fixes in it. If that is then case you have to choose whichever release (FP or CCH) addresses your current pain point. Good news though, as pointed out on the above link, once a FP is available a CCH will be made available shortly afterwards to address the "missing fixes" issue:

*Note: We plan on releasing an 8.0.2 Fix Pack 1 CCH1 within two weeks of 8.0.2 Fix Pack 1 so customers that need the latest fixes before they have gone through the lengthier Fix Pack test cycle can take advantage of them.

Another item of note is that the Technote also points out that there will be no CCH4. In effect it looks like once a FP is released all future CCH fixes will be built on top of the most recent FP release and the CCH number gets reset (as above, 8.0.2 FP1 CCH1) Get those Smart Upgrade help docs out.