From: | Tomasz Myrta <jasiek(at)klaster(dot)net> |
---|---|
To: | Jan Wieck <JanWieck(at)Yahoo(dot)com> |
Cc: | Ries van Twisk <ries(at)jongert(dot)nl>, pgsql-sql(at)postgresql(dot)org |
Subject: | Re: To use a VIEW or not to use a View..... |
Date: | 2003-01-22 16:20:57 |
Message-ID: | 3E2EC4E9.7000809@klaster.net |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-sql |
Jan Wieck wrote:
>Use tables, views and views over views, it's all fine and your indexes
>will be used.
I can't agree with using views over views. It has some limitations.
I asked about it on this list several months ago
and Tom Lane's conclusion was:
>> Tomasz Myrta <jasiek(at)klaster(dot)net> writes:
>> I'd like to split queries into views, but I can't join them - planner
>> search all of records instead of using index. It works very slow.
I think this is the same issue that Stephan identified in his response
to your other posting ("sub-select with aggregate"). When you write
FROM x join y using (col) WHERE x.col = const
the WHERE-restriction is only applied to x. I'm afraid you'll need
to write
FROM x join y using (col) WHERE x.col = const AND y.col = const
Ideally you should be able to write just
FROM x join y using (col) WHERE col = const
but I think that will be taken the same as "x.col = const" :-(
regards, tom lane
I don't know if anything changed on 7.3.
Regards,
Tomasz Myrta
From | Date | Subject | |
---|---|---|---|
Next Message | Stephan Szabo | 2003-01-22 17:09:14 | Re: To use a VIEW or not to use a View..... |
Previous Message | Stephan Szabo | 2003-01-22 16:10:04 | Re: To use a VIEW or not to use a View..... |