Re: MVCC, undo log, and HOT

On 10/23/07, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> > We never actually considred undo
>
> I did, but eventually ruled it out during the HOT design process. But
> then I considered a ton of other things and ruled them out also.
>
> Can't see a reason to bring it up again, so perhaps we should add it to
> the definitely don't want list. Don't *need* would be better.

Actually, my initial UNDO design and prototype had several other
advantages over HOT (better performance, inherent time-travel, smaller
on-disk footprint, and *no* vacuum). The major issue was due to the
amount of architecture changes Postgres would've required and Bruce's
advice regarding the community's inability to accept such a large and
complex change.

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Jonah H. Harris, Sr. Software Architect | phone: 732.331.1324
EnterpriseDB Corporation | fax: 732.331.1301
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