Please can you help me in Tuning this query..?

Question

Hi ,
Please can you help me in re-structuring this query? .Details are given below.
I have 2 tables as shown below and data is like this.
Position
COD IND
AAA N
BBB N
CCC N
DDD Y
Distance
orig dest
AAA BBB
BBB CCC
AAA CCC
I need to create the records like this
start end
DDD AAA
DDD BBB
DDD CCC
The query which i am using now for this is
select p.code AS start,
P1.CODE AS end
from position p, position p1
where
P.CODE != P1.CODE
AND (P.ind = 'Y' or P1.IND = 'Y')
AND not exists
(select 1
from distance d
where (d.orig = p.code or d.dest = p.code)
and (d.orig = p1.code or d.dest = p1.code))
table is having above a crore record. so its taking a lot of time.
Please someone please help in tuning this query?
Thanks and regards,
Shabir

Answer 1

Looks like you want this
select a.strt, b.ends from
(select p.code strt from position p where p.ind='Y') a,
(select p.code ends from position p where p.ind='N') b
where not exists (select 1 from distance d where d.orig=a.strt or d.dest=a.strt);
DDD     AAA
DDD     BBB
DDD     CCCYour query result is:
AAA     DDD
BBB     DDD
CCC     DDD
DDD     AAA
DDD     BBB
DDD     CCCYou should be more descriptive about what kind of result you want, so that people can get more interested in helping you.