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Corrected on 9/8/2017 to reflect correct syntax to eliminate just the one table.
The application in this case – SPSS – maintains an exclusive lock at all times on one table. I think this is poor application design, but IBM was not willing to change it when we brought it to their attention in a PMR.… Read the rest
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Some applications are really good at continually trying to re-establish connections to a database. This can be useful when I want to quickly bounce the database and have the app reconnect without also having to bounce the app. It is problematic when I need DB2 to be down and stay down, but still allow me to work with it.… Read the rest
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A number of new clients I’ve worked with lately have had minor or major runstats or reorg issues. I have tons of advice on runstats and reorgs across many blog entries, but I don’t have one place where all that advice is brought together.… Read the rest
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ADMIN_MOVE_TABLE is an administrative stored procedure introduced in DB2 9.7. The intent is to provide a tool that can be used to perform an online move of a table, while transactions are still occurring against the table. Moves can be used to change what tablespace a table is in, convert a table to MDC, change the table name, perform several changes that would normally require reorgs, reduce the size of a column, and perform other changes.… Read the rest
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There are some things to be aware of with ongoing support of a HADR system. I thought I’d group them together to provide a primer of do’s and don’ts for support of HADR.
HADR does occasionally stop all by itself.… Read the rest
Continue reading »Not long ago, I posted some of the details of using PowerShell as your command line for DB2 on Windows. I am definitely addicted to PowerShell as my command line when I have to work on Windows servers.
I also have to write some scripts for some Windows systems.… Read the rest
Continue reading »I’m a control freak. I think that control freaks tend to make good DBAs as long as they don’t take it too far. My position for years has been that I would rather control my runstats, reorgs, and backups directly than trust DB2’s automatic facilities.… Read the rest
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Current statistics are vital to performance. If I’m encountering a database I haven’t regularly been supporting, and don’t know the maintenance plans and schedules, I frequently query to get an idea of how current they are.
To report the dates of statistics collection and the number of tables statistics were collected for on each date.… Read the rest
Continue 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 rest
Continue reading »(Edited 8/12/2014 to add links to the old tutorials from IBM)
There are a number of ways to cover error logging. I have covered some specific elements in previous posts, so I’m going for a more comprehensive approach in this post.… Read the rest
Continue reading »My earlier post on table reorgs covered Reorg’s place in a database maintenance cycle and running reorgchk. If you haven’t already read it, check it out: How to Tell When a Table Reorg is Needed
After the section on tables, REORGCHK output has a section with details on each index for each table that REORGCHK looked at.… Read the rest
Continue reading »Reorgs are one critical piece of both performance maintenance and maintaining how much disk space is used. In my first blog entry in this series, DB2 Basics: What is a Reorg, I talked about some purposes of reorgs. In this entry, I’m going to talk about how to determine what kind of reorg is needed on what tables.… Read the rest
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