Daily problems with indexing and their possible solutions

Uwe Ricken

Have you ever been in the situation that an application performed well the last day and – suddenly – you run into problems? Although you have Index Maintenance jobs and statistics up to date you will monitor a big degrade of performance! This session will demonstrate in a over 80 percent demo based presentation the following scenarios which happened this way in real life!

  • Why performance degradation in spite of maintenance jobs?
  • Just one more database in the result set and the query runs really bad – why?
  • Usage of literals is completely different from the usage of variables – why?
  • Identical data types but the query runs in part perfect and in part bad…
  • Your execution plan shows an INDEX SEEK – but the table will be scanned!
  • You get a query from the business which performs really badly but when you test it, it runs pretty cool – why?