[RESOLVED] Warning: mysql_num_rows() expects parameter 1 to be resource

[chopocol]

Hi there

I am new to php, i am doing a simple login tutorial but i keep getting this error.

Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\hello\login.php on line 18

<?php



$username = $_POST['username'];
$password = $_POST['passworld'];


if ($username&&$password)
{

$connect = @mysql_connect("localhost","root","mauricio") or die('Error can not conect to the datase');
mysql_select_db("xproject") or die('Error selection the database');


$query= mysql_query("SELECT * From userdb WHERE username='$username'");   // query the database user name

$numrows = mysql_num_rows($query);

echo $numrows ;




}// End username password


else
    die("Please enter a user name and passworld");

?>

can anyone help me

Thank you for time.

[NogDog]

It usually means that MySQL was not able to process your query at all, typically due to a SQL syntax error or a mistyped column/table name. After doing mysql_query(), you should test if the result is false, and if so, do some error logging/reporting to determine what is wrong, making use of the mysql_error() function.

PS: eventually you need to look into using mysql_real_escape_string() to escape your inputs and prevent SQL injection.

[chopocol]

Thank you for the advice

i will look into the SQL injection