Fix my SQL [800 Credits]

[btfog]

Can figure out what is wrong. Keep getting this error: Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource... on line 12. I'll test the code in order of the replies, and first correct person gets the credits. Here is the code:

<?
include("connection.php");
$username=trim($username);
$password=trim($lpassword);
if($username=="" || $password =="")
{
    header("Location: index.php?error=wu");
    exit;
}
$sql="SELECT 'password' FROM 'admin' WHERE 'username'='$username'";
$result=mysql_query($sql);
while($row=mysql_fetch_array($result))
{
    $dbpass=$row[0];
}
if($dbpass==$password)
{
    session_start();
    $admin_username=$username;
    session_register("admin_username");
}
else
{
    $myFile = "index.php?error=wu";
    $fh = fopen($myFile, 'w');
    exit;
}
?>

[lemon-tree]

Wrap the 'password', 'admin' and 'username' with ` instead, like so:

$sql="SELECT `password` FROM `admin` WHERE `username`='$username'";

or remove the quotes completely:

$sql="SELECT password FROM admin WHERE username='$username'";

[btfog]

Didn't do anything...
Getting the error on http://www.astrosnation.co.cc/qa/admin/adminhome.php
Thanks for the response
Try admin for username and admin for password

[lemon-tree]

OK, try inserting mysql_error() like this and it'll tell you what is wrong with your SQL:

...
$sql="SELECT 'password' FROM 'admin' WHERE 'username'='$username'";
$result=mysql_query($sql);
echo mysql_error();
while($row=mysql_fetch_array($result))
...

[btfog]

it is saying no database selected, however, that should have been achieved by my "connection.php"

[lemon-tree]

Well clearly it hasn't, are you sure you are selecting a valid database?

[btfog]

I'm obviously retarded... uploaded my connection file without making changes. Thanks... will sent credits when the system works again