Statistics FAQ

Kendra Little has a great FAQ on statistics, from the standpoint of developers as well as administrators:

I’ve been asked a lot of questions about updating statistics in SQL Server over the years. And I’ve asked a lot of questions myself! Here’s a rundown of all the practical questions that I tend to get about how to maintain these in SQL Server.

I don’t dig into the internals of statistics and optimization in this post. If you’re interested in that, head on over and read the fahhhbulous white paper, Statistics Used by the Query Optimizer in SQL Server 2008. Then wait a couple days and chase it with it’s charming cousin, Optimizing Your Query Plans with the SQL Server 2014 Cardinality Estimator.

I’m also not talking about statistics for memory optimized tables in this article. If you’re interested in those, head over here.

This is a great distillation of important and oft-misunderstood content.

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