Re: AW: pg_index.indislossy

> Bruce Momjian writes:
>
> > > > > > Can someone tell me what we use indislossy for?
> > >
> > > Ok, so the interpretation of this field is:
> > > A match in the index needs to be reevaluated in the heap tuple data,
> > > since a match in the index does not necessarily mean, that the heap tuple
> > > matches.
> > > If the heap tuple data matches, the index must always match.
>
> AFAIK, this is true for all indexes in PostgreSQL, because index rows
> don't store the transactions status. Of course those are two different
> underlying reasons why a heap lookup is always necessary, but there
> shouldn't be any functional difference in the current implementation.

Seems it is something they added for the index abstraction and not for
practical use by PostgreSQL.

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