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Re: count(*) or count(id)
Posted by: Rick James ()
Date: July 04, 2016 01:04PM

And, if `id` is the PRIMARY KEY, then it is known to be unique. So you will get the same answer.

Please use COUNT(*) so the reader (including yourself a year from now) won't have to wonder if there could be NULLs that are being avoided.

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Subject Views Written By Posted
count(*) or count(id) 652 Ra Nala 06/28/2016 06:22AM
Re: count(*) or count(id) 289 Ra Nala 06/28/2016 06:26AM
Re: count(*) or count(id) 278 Peter Brawley 06/28/2016 05:18PM
Re: count(*) or count(id) 304 Rick James 07/04/2016 01:04PM
Re: count(*) or count(id) 301 Ra Nala 07/06/2016 12:30AM


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