Category: News from the labs

Each month, SEG sends out valuable technical DB2 z/OS information based on knowledge gained by the experienced developers and technicians in our product labs. We would like to share this newsletter with other DB2 users, like yourself.

2018-02 Db2 Catalog Statistics revisited

Db2 Optimizer & access path selection for Db2 11 & Db2 12 : Db2 Catalog data | Problematic default values | Correlations in the Db2 Catalog  It has been six years since the last update so I thought, after Terry Purcell’s excellent

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2018-01 Db2 GETPAGES by Insert

  Troubleshooting on site : how a simple Db2 SQL INSERT statement causes a high GETPAGES rate and how to fix it. One shop I visit had an interesting problem the other day.  I thought I would share it with

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2017-11 Db2 APAR list: An APAR a day keeps the bugs at bay

Db2 12 APAR – time saving list With all the talk about “agile” going on, and referring to one of my older 2017-09 newsletters* on APARS, I think it is time to tell you all about another little service that

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2017-10 Db2 log size: How big is your LOG?

  How to validate that your Db2 LOGs are OK ? Sizing of LOGs changed quite a bit in Db2 11 and Db2 12, so I thought a little recap about the correct sizing and ZPARMS was in order this

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2017-09 Db2 12 SQL Access path: Death by APAR

We recently held one of our Design Councils, this one was all about Db2 12 and going Agile. I was asked the following question after one of my presentations about verifying Db2 Code/Catalog/Function Levels: “How many APARs really can affect

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2017-08 Anomalies detected in MERGECOPY and MODIFY Recovery

Db2 z/OS Utilities: Identify and avoid some MERGECOPY or MODIFY Recovery anomalies Just a little note this month about a strange anomaly in the way MERGECOPY and MODIFY RECOVERY seem to work. Let’s begin with MERGECOPY. 1 – MERGECOPY to

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2017-07 Let’s make DB2 z/OS IMAGE COPY great again!

War story : Why is Db2 z/OS IMAGE COPY very useful in the current Db2 z/OS world? Please excuse the heading, I simply could not resist… This month is another war story from the trenches of Production DBAs fighting the

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2017-06 APPLCOMPAT in Db2 12: a little bit more agile?

How to set Collection Ids for a reopt 2, 3 or 4 (Runtime optimization) and avoid the default collection NULLID ? Following on from my last newsletter, I have had to do some research about Collection Ids and how to

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2017-05 Db2 version 12: A little bit too agile?

  How to handle APPLCOMPAT when it comes to Dynamic SQL? I have been involved in testing in Db2 version 12 for a while now, and I think we need a discussion about a few features that come in with this

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2017-04 DB2 ZPARM : Small ZPARM – Big effect!

Do you know how important it is to check the ZPARM EDM SKELETON POOL size to improve your I/O rate and lower your CPU? Do you know how to set it? From the frontline I was checking and verifying our WorkLoadExpert (WLX)

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