Re: RAC for Reporting...!

From: Matt <mccmx_at_hotmail.com>
Date: 7 May 2004 00:46:09 -0700
Message-ID: <cfee5bcf.0405062346.43b7f708@posting.google.com>

>
> What is it about "some of the users' queries" that causes this? Can
> you change the architecture or the queries in such as way as to
> eliminate or minimize the issue?

Basically the users queries are built with a GUI query builder which has a habit of producing very badly tuned SQL. I have been attempting to re-write some of the worst performers. Only problem is that the raw SQL itself can't be edited so its a case of painstakingly going through the query builder and re-building the table relationships and expressions.

One thing I can do is add hints to the SQL though which has yielded some pretty impressive improvements.

But even with the tuning of these adhoc queries there is still a requirement to provide a mechanism of reducing the impact of query uses on online users. Thats why I'm investigating Mat Views.... Just need to overcome the query re-write restrictions (see my other responses).

Thanks

Matt Received on Fri May 07 2004 - 02:46:09 CDT