COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better?

Posted by zneak on Stack Overflow See other posts from Stack Overflow or by zneak
Published on 2010-04-26T01:10:49Z Indexed on 2010/04/26 1:13 UTC
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sql

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select

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count

Hello guys,

I often find these three variants:

SELECT COUNT(*) FROM Foo;
SELECT COUNT(1) FROM Foo;
SELECT COUNT(PrimaryKey) FROM Foo;

As far as I can see, they all do the same thing, and I find myself using the three in my codebase. However, I don't like to do the same thing different ways. To which one should I stick? Is any one of them better than the two others?

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