Posted by Schraalhans Keukenmeester on 10/22/05 16:05

X-Followup: comp.lang.php

I have a PHP script that adds messages to a simple MySQL Database.
(PHP 5.0.3, MySQL 4.1.1)

One of the fields it stores is msgid.
The new msgid is a count of all current msgs in the db plus one

$query = 'select count(*) from messagesdb;';
$result = mysql_query ($query, $conn);
$msgid = mysql_result ($result, 'count(*)') + 1;

The next message is added using the above msgid.
For some reason (there are NO other scripts/systems accessing this
table, it is all on a local testmachine) I now have about 200 messages
in the system, but some id's occur more than once, up to 4 times.

I cannot explain this behaviour. I know I could avoid the entire issue
by autonumbering the messages, but still there is something funny going on.

I am wondering, is php messing up, or is this a mysql glitch, or am I
missing something here ?

Thanks for your time
Sh

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