Re: index blocks read one at a time or is this old info? (Sorta a myth?)

From: Mike Ault <mikerault_at_earthlink.net>
Date: 22 May 2002 12:17:55 -0700
Message-ID: <37fab3ab.0205221117.1e921a9c@posting.google.com>

This is easy to check, use v$filestat to do an IO ratio for blocks read or blocks written per IO, you will find indexes are single block IO.
Even in 9i...

Mike

"Pablo Sanchez" <pablo_at_dev.null> wrote in message news:<3ce575f0$1_4_at_news.teranews.com>...
> "D.Y." <dyou98_at_aol.com> wrote in message
> news:f369a0eb.0205171333.6d148c73_at_posting.google.com...
> >
> > > 3) If 1) again, any plans to start storing the data sorted so we
> can
> > > do "index_multiblock_read"s? I realize that there's a hit on
> changes
> > > to the b-tree because we'd have to rebalance the tree and possibly
> > > affect many DB blocks.
> >
> > Forcing index blocks to be physically sorted will create too much
> overhead
> > for DMLs. I hope Oracle won't do that.
>
> There's a definite trade-off ... it seems that we still do point I/O's
> based on another post within the 'Oracle Myths' thread.
Received on Wed May 22 2002 - 14:17:55 CDT