Top Ten Most Common DB2 Performance Problems

1. PEBCAK 
   
   The number one cause of DB2 performance problems today, as always, is Problem Exists Between Chair And Keyboard!
    
2. Poorly coded SQL
   
   Many performance problems can be traced back to inappropriately coded SQL Code it correctly from the beginning and tune what is already out there.
        
3. Improper indexing
   
   Optimize performance via indexing by workload, not by object.  
    
4. Bad program design
   
   

   Coding DB2 SQL for Performance in your application programs from the outset can eliminate many future problems.

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5. Bachelor programming syndrome
   
   Yes, the dreaded "Fear of Committing" can cause performance problems due to concurrency issues.
        
6. Improperly defined buffer pools
   
   Defining effective buffer pools for your DB2 workload is important. There are many things you can do to identify the proper settings and sizing of your DB2 buffer pools.
        
7. Index / table space needs to be reorganized
   
   Reorganization of indexes and table spaces can improve performance. Follow the Five R's to assure optimal DB2 application performance.
    
8. Improperly designed database structures
   
   Designing database structures correctly -- from the beginning -- is the way to go for efficiency and efficacy.
    
9. Copied code syndrome
   
   
   You know the drill...
   
   Developer: "Help me... I copied this from another programand it works there... so why not here"...
   
   DBA: OK, what do you think this code does?
   
   Developer: "I don't know, that's why I copied it... Can't you just make it work?"
    
   
10. RUNSTATS not up-to-date (or not even run)
    
    How can you expect for the DB2 Optimizer to do its thing on your SQL without statistics about your data and environment? Again, The Five R's!

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