query takes a long time
Started by Garry Saddingtonover 17 years ago2 messagesgeneral
Can someone suggest how I could speed up the execution of this query?
select count(distinct attendance.studentid)
from attendance
where attendance.studentid not in (select studentid from attendance where auth not in('C','E','F','G','H','I','M','N','O','R','S','T','U'))
It returns the correct results but very slowly.
regards
garry
Re: query takes a long time
select count(distinct attendance.studentid)
from attendance
where attendance.studentid not in (select studentid from attendance where
auth not in('C','E','F','G','H','I','M','N','O','R','S','T','U'))
I am tired a lot now, but isn`t it the same as:
select count(distinct attendance.studentid)
from attendance
where auth in('C','E','F','G','H','I','M','N','O','R','S','T','U')
?