Subject not null in statement very slow
Author sascha_luttmann
Hello,

I have the following problem:

in my database there are two tables (MOV_ORDERS and
MOV_ORDERS_POSITIONS).
I fetch records from both tables and check in my query if the deliver
date is not null. Something like this:
select …. from … where (ID=:ID) and (DELDATE is not null)
The problem is that this check for "not null" needs a very long time
to get the results. The query is much faster when try this:
select ... from … where (ID=:ID) and ((DELDATE >= '31.12.1899') and
(DELDATE <= '31.12.2004'))

Both statements return the same result but the first one needs ten
times as long as the second one. How come?

Best regards,
Sascha