Re: How does Oracle Fast Refresh on Materizlied View for Joined Tables?

From: Sybrand Bakker <gooiditweg_at_sybrandb.demon.nl>
Date: Fri, 25 Jul 2003 20:13:41 +0200
Message-ID: <ips2ivcbpu3lfj5jai5248g9cqg9qg53lb@4ax.com>

On 25 Jul 2003 09:19:49 -0700, yyoodd_at_hotmail.com (yyoodd) wrote:

>I wonder if anyone knows how oracle accomplish the task of Fast
>Refreshing MView for joined tables. I know it has logs for all changes
>happened on the underlying tables. However, let's say I have an MView
>as simple as Select * from T1, T2 where T1.C1=T2.C2 and T1.C2=1. When
>there is an insert on T1, how can Oracle tell if it needs to bring new
>rows from T2(that now should be in the MView) solely depending on
>change logs? Since the data in T2 are not changed themselves. And
>where does Oracle retrieve the row data? From the underlying table T2?
>What if change happened on T2 at the same time so that the data image
>of that row is no longer available? Apply undo?
>
>So confused....
>
>yyoodd

IIRC you can't have fast refresh on complex mviews. This includes joined tables.

Sybrand Bakker, Senior Oracle DBA

To reply remove -verwijderdit from my e-mail address Received on Fri Jul 25 2003 - 13:13:41 CDT