$result = DB_query_array_all("SELECT User.fullname,".
"IFNULL(AVG(if(P1.sequence in (2,3,4),".
"-timestampdiff(MINUTE,mod_date,(select mod_date from Play P2 where P1.trick_id=P2.trick_id and P2.sequence=P1.sequence-1)),NULL )),1e9) as a, ".
$result = DB_query_array_all("SELECT User.fullname,".
"IFNULL(AVG(if(P1.sequence in (2,3,4),".
"-timestampdiff(MINUTE,mod_date,(select mod_date from Play P2 where P1.trick_id=P2.trick_id and P2.sequence=P1.sequence-1)),NULL )),1e9) as a, ".