On Sun, 2006-06-25 at 05:29, Alvaro Herrera wrote:
> Mark Woodward wrote:
> > I originally suggested a methodology for preserving MVCC and everyone is
> > confusing it as update "in place," this isnot what I intended.
>
> It doesn't make sense, but maybe vacuuming a page would. Naturally, it
> would need to wholly scan all the indexes to clean'em up, so it's
> probably not a good idea in general.
But a version of vacuum which does normal index scans when vacuuming
just a small percent of a huge table would make sense wouldn't it ? So
you don't need to make full scans of the vacuumed indexes but look up
the entries based on the vacuumed key.
There were discussions about this I think, and the objection was that it
might be that an index scan might miss index entries, in particular when
badly behaved user defined functions are involved.
Cheers,
Csaba.
