Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, boolean given in

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<?php
if(isset($_POST['login']))
{
	$username = $_POST['username'];
	$password = $_POST['password'];
	
	if(empty($username) or empty($password))
	{
	echo "fill the empty fields";
	exit();
	}
	
	if(isset($_POST['re']))
	{
		$re = "on";
	} 
	else 
	{
	$re = "";
	}
		
	$query = mysqli_query($con, "SELECT COUNT (*) FROM 'admin' WHERE username='$username' AND password='$password'");
	
	if (!$query || mysqli_num_rows($query) == 0)
	{ echo "very worng";
		}
	
	if(mysqli_num_rows($query) == 1);
	{
		
		// login user in
		if($re == "on")
		{ // remember me on
		setcookie("username",$username,time() + (86400 * 10));	
		}else
		{ // remember me not checked 
		session_start();
		$_SESSION["username"] = $username;
		}
		echo "user logedin";
		exit();
	}
	echo "invablid username or password";
	exit();
	
}
?>

What I have tried:

unable to understand, checked database and syntex phres

Posted 28-Jan-17 4:29am

Member 12971740

Updated 28-Jan-17 5:22am

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Comments

CHill60 28-Jan-17 10:40am

There is either a problem with your sql query or it is not returning any data. Check for success before using the result in any further code.
As an aside, you should NOT be storing passwords in plain text like this.

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Peter Leow · Answer 1 · 2017-01-28T05:22:00

This

mysqli_num_rows($query)

expected

$query

to be a result set, but it turned out to be a boolean false. PHP: mysqli_result::$num_rows - Manual[^]. Try improving your code like this:

if (!$query) { 
	echo("Error description: " . mysqli_error($con));
} else if(mysqli_num_rows($query) == 1){
    // omitted
} else {
   echo "invablid username or password";
}