GENERATED ALWAYS can be a blessing or a curse. I’m not talking about identity columns here, but about creating a column that is actually a duplicate of some part of the data to boost performance. Sure, in 10.5 we can do indexes on expressions, but for some clients I have trouble just getting them to go to a supported level, much less the latest and greatest.… Read the restContinue reading »
I wrote a developerWorks article on finding problem SQL in your package cache. But I refine and play with my SQL over time, so I thought I’d share the version I’ve been using recently.
To find problem SQL in the Package Cache across several importance performance categories.… Read the restContinue reading »
This is part one of a three part series. The full series includes:
DB2 Workload Manager (WLM) as a Monitoring Solution – Understanding WLM (Part1 of 3)
DB2 Workload Manager (WLM) as a Monitoring Solution– How to Set up WLM (Part 2 of 3)
DB2 Workload Manager (WLM) as a Monitoring Solution– Analyzing WLM Information (Part 3 of 3)
What is DB2 Workload Manager (WLM)?… Read the rest Continue reading »
To go with my recent article on RCAC/FGAC, I thought I would do some similar work using LBAC and see what I could learn about it and the differences between the two.
What is LBAC
Label Based Access Control essentially adds a column to a table that labels each row (think confidential, secret, top secret), and then grants uses of those labels to users to allow them to access the data.… Read the restContinue reading »
If you’re not familiar with MONREPORT, see my DB2 Basics entry on MONREPORT first.
Most of the references I’ve seen to customizing the MONREPORT module basically say “get the code out of the database, modify it, and deploy it”. (see IBM DB2 Knowledge Center Entry on Customizing the MONREPORT module reports)
I have found this rather frustrating when I’ve run across it, and when I find a lack of documentation frustrating, I tend to blog to fill the hole as much as possible.… Read the restContinue reading »
If you’re mourning the loss of “RESET MONITOR ALL”, there are a number of ways you can address that. Ideally, you’d use this approach: http://www.ibm.com/developerworks/data/library/techarticle/dm-1009db2monitoring1/, but there are some arguments for using MONREPORT over that in some ways. One argument is that MONREPORT is built-in and you don’t have to add objects to make it work.… Read the restContinue reading »
I’ve been working with a developer to profile some SQL from a process he’s running. He has no insight into the SQL that the tool is using, primarily to insert data. I thought I’d share some of the details. I still think of this kind of event monitor as a “Statement Event Monitor”.… Read the restContinue reading »
I have been playing a fair amount lately with clustering indexes and have been rehashing my views on reorging tables on an index. This is still a work in progress, but thought I’d share some details and see if others out there have any thoughts to share with me and others on it.… Read the restContinue reading »
The request from the developers was something along the lines of “Help, Ember, this query needs to perform better”. Sometimes the query I’m working on is not one that shows up as a problem from the database administrator’s perspective, but one that is especially important in some part of application functioning.… Read the restContinue reading »
I have not made extensive use of the HADR Tools that IBM offers in the past. Most of my HADR setups to date have either been same-data-center using NEARSYNC or have used ASYNC to copy data between data centers. I haven’t had much cause to tweak my network settings or change my SYNCMODE settings based on hardware/networking.… Read the restContinue reading »