check if SQL row exists with PHP

Question

I\'m using MySQL with PHP and I need to do something like this (pseudocode):

if (sql row exists where username=\'bob\')
{
    // do this stuff
}

Answer 1

another approach

$user = "bob";
$user = mysql_real_escape_string($user);
$result = mysql_query("SELECT COUNT(*) AS num_rows FROM my_table WHERE username='{$user}' LIMIT 1;");
$row = mysql_fetch_array($result);
if($row["num_rows"] > 0){
   //user exists
}