我收到此错误:
Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /home/u391124286/public_html/options.php on line 7
我的代码是
<?php
$con=mysql_connect("localhost","root","pass");
mysql_select_db("my_db");
$query=mysql_query("SELECT * FROM Options where
Option='Map' AND
Toggle='1'");
$count=mysql_num_rows($query);
if($count==1){
$Map='1';
}
else
{
$Map='0';
}
?>
我不明白为什么会发生这个错误,我对 php 相当陌生,所以它可能很简单。