mysql num rows error
problem:
Quote: Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /var/www/html/findyourdesire/stats.php on line 21
section of code causing it:
<?php
# talk to the db
$db=mysql_connect($host, $login1, $pass1) or die(\"cannot access mysql\"); # connect
$fyd=mysql_select_db('findyourdesire', $db) or die(\"cannot access db\"); # select the db
$querystats=mysql_query(\"SELECT * FROM stats WHERE uid='$uin'\", $db); # find the stats
$stats=mysql_fetch_array($querystats); # get the stats
$queryvotes=mysql_query(\"SELECT * FROM votes WHERE votee='$uin'\", $db); # find the votes
$vc=mysql_num_rows($queryvotes); # how many votes
for($i=0;$i<$vc;$i++){ # for each vote
$voteinfo=mysql_fetch_array($queryvotes); # get the vote info
$vt+=$voteinfo['vote']; # find the vote total
}
if($vc==0){ $vc=1; }//prevent div by zero issue
?>POSIX. because a stable os that doesn't have memory leaks and isn't buggy is always good.
Mark Hensler posted this at 01:49 — 29th August 2003.
He has: 4,048 posts
Joined: Aug 2000
Try testing it against FALSE. If the query failed, for whatever reason, mysql_query() will return false.
zollet posted this at 05:56 — 29th August 2003.
He has: 1,016 posts
Joined: May 2002
Before the mysql_num_rows() line, type: echo mysql_error();
If there are any problems, that line will print it on the screen.
Suzanne posted this at 06:42 — 29th August 2003.
She has: 5,507 posts
Joined: Feb 2000
I think I've said this before, but instead of forcing someone else to go through my code line by line, I use:
<?phpif (!$qry) {
echo mysql_error();
exit;
}
?>
Perhaps there is a better way to check line by line, but that's often all I need after a particular query to find MY ERROR and fix it.
Mark Hensler posted this at 07:20 — 29th August 2003.
He has: 4,048 posts
Joined: Aug 2000
"When in doubt, print it out."
I think often times there is nothing wrong with the logic where the error occurs. But rather, the data we are manipulating is not what we expected it to be at that point.
Mark Hensler
If there is no answer on Google, then there is no question.
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