Re: Does Oracle store values in indices?

[ Charset KOI8-R unsupported, converting... ]
> > > > The reason you have to visit the main table is that tuple validity
> > > > status is only stored in the main table, not in each index.
> > > > See prior discussions in the archives.
> > >
> > > But how Oracle handles this?
> >
> > Oracle doesn't have non-overwriting storage manager but uses
> > rollback segments to maintain MVCC. Rollback segments are used
> > to restore valid version of entire index/table page.
>
> Are there any plans to have something like this? I mean overwriting storage
> manager.

We hope to have it some day, hopefully soon.

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