Monday, September 30, 2013

a few points about sql server execution plan


  • sql server will not use your order of joins if it thinks it can do it better. For example, if in your code a is joined to b and b to c but the index on a is enough to get the columns needed on c - it may join a to c.
  • the only thing for certain is logical reads, not physical
  • the determining factor for high % (for example , shown in sql sentry plan as red) is the amount of executions





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