Re: Fastest way to get table records' number

First, I swore I deleted that message before I sent it. Rethought the whole count(*) thing and re-read the OP that said count(*) was faster. Oh well.. hah.. Second.. about mysql_num_rows()... at that point, the database has collected the data and sent it to the PHP script. If you're pulling the data anyway, that's cool, but if all you want is a count then you're better off letting the database do the heavy lifting and only returning a single column, single row with the count. Say for instance, you have a table with 1000 rows: SELECT * FROM sometable This will grab all the data, send it all to PHP. SELECT count(*) FROM sometable Sends a single row to PHP. Leaving the heavy lifting to the DB server. This is a good thing if you don't need any of the data, just a count. -TG ----- Original Message ----- From: It Maq <itmaqurfe@yahoo.com> To: PHP General list <php-general@lists.php.net> Date: Wed, 19 Mar 2008 10:38:16 -0700 (PDT) Subject: Re: [PHP] Fastest way to get table records' number > Hi, > > did you try mysql_num_rows ? > > --- Andrew Ballard <aballard@gmail.com> wrote: > > > On Wed, Mar 19, 2008 at 1:04 PM, TG > > <tg-php@gryffyndevelopment.com> wrote: > > > > > > It seems that count(*) pulls all the data from > > the row then performs a count > > > increment whereas count(did) only pulls the 'did' > > column. > > > > Again, I don't believe COUNT(*) pulls any data. If > > there is a row, it > > simply counts it. The row could be full of NULLS (if > > allowed by your > > schema - yikes) and it will still be counted. I'd > > guess that COUNT(1) > > does the same thing. COUNT(did) does only examine > > the did column, > > but NULL values are excluded from the count.