datepart for milliseconds not precise in SQL Server 2008?

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datepart for milliseconds not precise in SQL Server 2008?

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Erin Ramsay

Posted Monday, March 14, 2011 3:51 PM

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Why does this:

DATEPART(MILLISECOND,cast('2011-03-14 17:43:52.134' as datetime))

return 133?

and

DATEPART(MILLISECOND,cast('2011-03-14 17:43:52.135' as datetime))

return 137?

Is there an inconsistency in anything smaller than a second in SQL Server 2008?

Donalith

Post #1078032

Erin Ramsay

Posted Monday, March 14, 2011 4:02 PM

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Nevermind.. I didn't realize that SQL Server only maintained a 3.33 precision on milliseconds..

case closed.. thanks

Donalith

Post #1078034

Jeff Moden

Posted Monday, March 14, 2011 4:30 PM

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IIRC, the resolution of some of the new datetime function in 2k8 has a much better resolution.

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Post #1078042

Evil Kraig F

Posted Monday, March 14, 2011 4:43 PM

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Use the TIME datatype instead of DATETIME for higher resolution on timings. It's accurate to 100 nanoseconds.

Edit: Left the window open in the background too long I see, I've just added some clarity to what Jeff already mentioned. Smile

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Post #1078050

Lynn Pettis

Posted Monday, March 14, 2011 7:56 PM

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Also the datetime2 and datetimeoffset data types as well in SQL Server 2008.

Cool

Lynn Pettis

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