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what does count(1) do?

If there is a code like
SELECT count(1) from TABLE Where condition1=condition2;
Is count(1) same as count(*)?
Does count(1) counts the first column of the table?
Sep 18 '08 #1
1 1983
amitpatel66
2,367 Expert 2GB
COUNT(1) improves the query performance compared to COUNT(*). So in case if you have any primary key column then using that for the COUNT will improve the performance.
Sep 18 '08 #2

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