Re: How to get a distinct count of result set of multople table joins?
Date: Wed, 27 Feb 2008 05:05:04 -0800 (PST)
On Feb 26, 11:26 pm, "Chris ( Val )" <chris..._at_gmail.com> wrote:
> Hi everyone,
> I haven't played with SQL for a while, but the following SQL returns
> ~700,000 records ( a lot of duplicates ), and I used a UNION with the
> same query to reduce the records down to ~250,000. Is there a more
> efficient solution, as the UNION takes some time to run? ~3 mins.
> Thanks in advance,
What does the EXPLAIN PLAN show?
Performance issues are always data dependent. IOW, the phrase:
KNOW THY DATA
is one to take to heart.
Come back with the PLAN and we may have some suggestions.
Ed Received on Wed Feb 27 2008 - 07:05:04 CST