Tag Archives: dynamic sampling

Useful stuff from event 10053 traces – part 2

Posted on April 18, 2014 by Marcel-Jan Krijgsman

I would like to reflect once more on the “dynamic sampling used for this statement” message. Suppose dynamic sampling really happened with reason, because statistics were old, missing or otherwise insufficient. Now what?   Dynamic sampling because of missing or old statistics … Continue reading →

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Useful stuff from event 10053 traces – part 1

Posted on April 14, 2014 by Marcel-Jan Krijgsman

In theory you can use event 10053 traces to see what choices the optimizer has made, which is very interesting if your query didn’t perform as it was supposed to do. In practice event 10053 traces contain an overwhelming amount … Continue reading →

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Dynamic sampling NOT used for this statement?

Posted on April 8, 2014 by Marcel-Jan Krijgsman

So I’m still working on this data warehousing project and performance is not quite optimal. There are all kinds of things to be investigated. One thing I want to find, is the reason why a lot of execution plans show … Continue reading →

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