Subject performance problem with subquery and "not in" in fb 2.0!!!!
Author crizoo4712
Hello all,

the following simple query doesn't cause any performance problems in
firebird 1.5 but in firebird 2.0.1 it takes a very long time to get a
result set:

select sd_id from service_data
where sd_id not in
(select sd_id from service_resource_contents)

The column sd_id is primary key in table service_data and foreign key
in service_resource_contents (service_data is rferenced).

The execution plan in fb 1.5 shows an indexed access, in fb2.0 a
natural join on table service_resource_contents!

It seems to be a general problem with "NOT IN", because the usage
of "IN" is fast!

Can anybody help?
thank, regards, Christoph