Mark wrote:
-----Original Message-----
From: Chris [mailto:[EMAIL PROTECTED]
Sent: maandag 14 augustus 2006 6:32
To: Mark
Cc: mysql@lists.mysql.com
Subject: Re: Random SELECT on subset
Thanks to you, the query has been greatly simplified, but
the result is still the same: every once in a while (like if I
run this twenty times in a row), I only get 3 items
returned, or even 2!
And how many have 'processed=1' at that stage?
I highly doubt it's the rand() doing it - it's your data changing.
If you only have 2 unprocessed items in the queue, then mysql
can only ever retrieve 2 results no matter what "limit" you put
on it.
The WHERE part of the query is processed before the limit.
The data is NOT changing, of course. :) Just a small, fixed test table
and a test.pl prog to run this off a prompt.
Same table, same test prog, ran several times in a row.
Easiest way to tell is add an extra query:
select count(*) from tablename where processed='1';
..or even:
select * from tablename where processed='1';
so you can compare what the rand() is doing compared to the table.
--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
