Aufzeichnung vom 23. September 2015
20 Minuten Video in 4 Teilen
Webinar präsentiert von SOFTWARE ENGINEERING (engl)
Have you ever wondered if those really expensive REORG utilities are actually useful or not? Ever been able to verify it?
|1||(3 min.) Is a table in use?|
Review the workload at the table level to find windows of change where typically an ALTER and REORG can be run, with no disruption to current Service.
|2||(5 min.) Detect useful REORGs|
Have you ever wondered if those really expensive REORG UTILS are actually useful or not? Ever been able to verify it? It’s very tough indeed! But now with WLX it’s a cinch! You can easily see the access graphs and look for the typical saw-tooth lines that confirm a REORG has helped and also see any flat-lines that means the REORG did nothing to help data Access.(5 min.)
Now that you’ve seen what a REORG does for your workload, you might want to suppress the ones that are worthless. Easy as pie if you’re using the Exception Tables or RTDX at your site!
|3||(5 min.) Review the Choice|
We all know that the CLUSTERing index is an important choice, and we’re all equally aware that it is normally the first index that is ever created, (in fact for REORG it is the lowest OBID index if no explicit CLUSTER index exists) however, over time, the number of indexes and the data usage can (and do!) change. Thus it would be nice to see if the original data design was correct. Perhaps a couple of ALTERs and a REORG would work wonders at your shop?
|4||(5 min.) What ran when and did what?|
How to use a DB2 Performance warehouse for real world Use Cases.