Loading data into a DB2 database using the LOAD utility has a lot of ins and outs. If a DBA has spent a lot of time working in a database without referential integrity or check constraints, then they may forget…
I have been paying a bit of attention to cross-platform SQL optimization lately, and read this interesting post: https://www.periscopedata.com/blog/use-subqueries-to-count-distinct-50x-faster.html?utm_content=bufferaf11f&utm_medium=social&utm_source=linkedin.com&utm_campaign=buffer Being a bit of an experimenter, the first thing that I wondered is how DB2 would handle this scenario. Would the…
I actually had a blog entry started on this topic before IDUG. I knew this was possible, but not exactly how to do it. Then I sat in Scott Hayes’ session – D04 – More Sage Advice: Invaluable DB2 LUW…
When you’re considering dropping and re-creating a table, view, or MQT, it is critical to ensure that you consider any dependencies. When dropping a table, any MQTs that rely on it will be dropped, and views marked inoperative. With multiple…
I’ve played with the clpplus at least once before, but have generally thought of it as a tool created to satisfy those coming from Oracle and looking for Oracle-like features. One of the features I actually liked about Oracle in…
Have you ever looked at a list of tables in your database, only to see the set of EXPLAIN tables present in two, five or even 10 different developers’ schemas? I don’t know about you, but this drives me crazy.……
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. Purpose To report the…
I had been in conversation with a respected DBA who is a well known speaker and author. I had mentioned how difficult it is to come up with advanced topics to write and speak about. That is when he responded…
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. Purpose To find problem SQL in…
This is a topic I have to look up from time to time, and I always go straight to Serge Rielau’s blog. He has a number of good articles on LISTAGG, the similar XML specific functions, and much more. While…
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…
This was really a revelation for me when I took DanL‘s SQL workshop before the IDUG conference in Phoenix. I started out as a physical or systems DBA at IBM, and until studying for certification, I hardly wrote a statement…
