Thread

Re: [HACKERS] Concurrent VACUUM: first results

Vadim Mikheev <vadim@krs.ru> — 1999-11-26T06:42:07Z

Tom Lane wrote:
> 
> "Hiroshi Inoue" <Inoue@tpf.co.jp> writes:
> >> I wonder whether there isn't a cleaner way to do this.
> 
> > I think there exists another reason.
> > We couldn't delete index tuples for deleted but not yet committed
> > heap tuples.
> 
> My first thought was "Good point".  But my second was "why should
> vacuum need to deal with that case?".  If vacuum grabs an exclusive
> lock on a relation, it should *not* ever see tuples with uncertain
> commit status, no?

What if vacuum will crash after deleting index tuples pointing
to heap tuples in old places but before commit? Index will
be broken.

Vadim