Just Learned - SELECT count(*) - A myth busted

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SELECT count(*) - A myth busted

Oct 26 2011 6:28AM by Latheesh NK

When we use select count(), the query processor will use scan on the index with the smallest number of pages to find the result of select().

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Published under: SQL Server Tips · · · ·

Latheesh NK

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I had to go to Paul's link to confirm the typo in this post. I believe you want to refer to COUNT(*), not SELECT(*)

For COUNT(*), scanning the index makes sense. In fact, it is one of the most accurate methods to get the count of records in a given table. You may be interested to read more about it in my post: Measuring the number of rows in a table – are there any alternatives to COUNT(*)?

commented on Oct 29 2011 8:25AM

Nakul Vachhrajani

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Nakul, great post!!! really enjoyed it. Thats my bad select(*)...I will edit it...

commented on Oct 31 2011 12:07AM