lopxen on "Empty wpdb->get_resuts die de execution"

Hi,

I am running a "SELECT" sentence via wpdb->get_results($sql) or die (mysql_error()).

When the sentece produces results, no problem, but if there result is "empty", the "die()" stops de execution, but it the mysql_error() shows nothing. Furthermore, mysql_errno() is 0.

The question is, if there is no sql error, why die() stops the execution?

I been searching for hours in the internete, but nothing. I am getting completely crazy!!!

Thanks!!