A blog by Jose Barreto, a member of the File Server team at Microsoft.
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Here are some notes on "SQL Server 2008 Statistics" I took while attending an advanced class on SQL Server taught by Kimberly Tripp (http://sqlskills.com/AboutKimberlyLTripp.asp).
Please note that, although these notes were taken during the class, I might have added some of my own (mis)interpretation :-). Always check your facts on Books Online (I try to provide links when applicable). As with anything else you get from a blog, never use any of this in production before you thoroughly validate it a test environment. Please keep in mind that some of those will be hard to follow without the right pre-requisite knowledge and the right context. Reading the post from top to bottom will help.
Understanding the job of the cost estimator
Not always right
Could be statistically correct after update
Looking at stats
Stats with no index?
Let SQL do it
Leave it on
Stats get old
Very large sets
For details, see "Statistics Used by the Query Optimizer in Microsoft SQL Server 2005" at:http://technet.microsoft.com/en-us/library/cc966419.aspx