Re: Multi-Versions and Vacuum

grant wrote:
> If Oracle uses multiple version concurrency, then why does it appear to do
> row locking (I use Oracle at work, but I do not admin it)
>
> The only downside I have seen to MVCS is the extra disk space, but with
> the performance improvements in a highly concurrent use environment, it is
> well worth it.
>
> Q:  Does VACUUM FULL remove the rows that are too many for the FSM?  Or,
> are they just stuck?  I know that regular VACUUM will not allow reuse of
> overflowed rows.  Also, how does one calculate the propper size for the
> FSM?

VACUUM full removes all unused rows from disk _including_ ones that
aren't in the free space map.

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