Re: Warning: mysql_num_rows(): supplied argument is not a valid MySQL (the answer)

[rob richards]

Probably your sql statement sucks, and should look something like:

$query = " SELECT * FROM blah WHERE id=something";

echo "My query that sucks is: $query" ;

$result_set = mysql_query($query);
if (mysql_num_rows($result_set) == 0) { ....

See if $query is actually one that produces correct results!

ciao.