Best way to check if MySQL results returned in PHP?

Question

I\'m looking for the best way to check and see if any results were returned in a query. I feel like I write this part of code a lot and sometimes I get errors, and sometimes

Answer 1

Usually I use the === (triple equals) and __LINE__ , __CLASS__ to locate the error in my code:

$query=mysql_query('SELECT champ FROM table')
or die("SQL Error line  ".__LINE__ ." class ".__CLASS__." : ".mysql_error());

mysql_close();

if(mysql_num_rows($query)===0)
{
    PERFORM ACTION;
}
else
{
    while($r=mysql_fetch_row($query))
    {
          PERFORM ACTION;
    }
}