[RESOLVED] warning: mysql_num_rows()...

zero0

Hello.

I need help on this one. Anyone knows why i keep on getting this error:

Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in C:\wamp\www\hoya\checkLogin.php on line 16

And what should i modify with the codes i have here in order for it to work?

<?php
$username = $_POST["username"];
$password = $_POST["password"];

$con = mysql_connect("localhost","root","pass");
if (!$con)
{
  die('Could not connect: ' . mysql_error());
}

// some code
mysql_select_db("mydb", $con);

$result = mysql_query("SELECT * FROM sign-up WHERE Username='$username' AND Password='$password'");

$count = mysql_num_rows($result);
if($count==1)
header( 'Location: loggedIn.php' ) ;
else if($count == 0)
{echo "Wrong Username or Password!";}

mysql_close($con);
?>

dagon

it means your query failed, if you echo $result, it will be 0 (= fail)

check table and field names they are case sensitive.

NogDog

That error usually indicates that MySQL was unable to process the SQL you provided it, so you need to debug the query code. Check to see if the result of your mysql_query() is false, and if so, do an error_log() or otherwise output the query string and the result of mysql_error() to find out what was wrong with the query.

bradgrafelman

Also note that your code is vulnerable to SQL injection attacks. User-supplied data should never be placed directly into a SQL query. Instead, it must first be sanitized with a function such as [man]mysql_real_escape_string/man.

zero0

alright, thanks for the replies everyone.

got it to work already. apparently it just needed some fixing in the syntax.