Re: [SQL] Non Matching Records in Two Tables

[Ken Hill]

On Tue, 2006-02-14 at 13:24 -0800, Ken Hill wrote:

On Tue, 2006-02-14 at 13:08 -0800, chester c young wrote:

> Here is my query SQL:
> 
> SELECT key100 FROM ncccr10
> WHERE ncccr10.key100 NOT IN (SELECT key100 FROM ncccr9);
> 
> It is is running after 30 minutes. Here is the query plan:
>

I would try an outer join:

select a.key100
from ncccr10 a
left join ncccr9 b on( key100 )
where b.key100 is null;

also (hate to be obvious) have you analyzed lately?


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 

---------------------------(end of broadcast)---------------------------
TIP 1: if posting/reading through Usenet, please send an appropriate
       subscribe-nomail command to [EMAIL PROTECTED] so that your
       message can get through to the mailing list cleanly

Yes, I did a VACUUM ANALYZE on the entire database before running this query. Also, I get an error with your suggestion:

csalgorithm=# SELECT a.key100 FROM ncccr10 a
csalgorithm-# LEFT JOIN ncccr9 b ON(a.key100)
csalgorithm-# WHERE b.key100 IS Null;
ERROR:  argument of JOIN/ON must be type boolean, not type character

Well, this works:

SELECT *
FROM ncccr9 a
LEFT JOIN ncccr10 b USING( key100 )
WHERE b.key100 is null;

It still seems slow. It takes about the same time to run as in MS Access. I thought PostgreSQL would be faster.