Search mysql via php

[Jmacp]

Trying to make a login page...inputs are username and password.

So i need to search the db to see if the username exisits first then, if so, check the password is ok, thought i could do something like,

$link = mysql_query("select * from tlogin where username = '".$username."'");

if(!$link){

echo "wrong username";

}else{

} 

Can i do that or is there a better way ?