Re: AW: Adding index flag showing tuple status

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>
> > I am looking at adding an index tuple flag to indicate when a
> > heap tuple is expired so the index code can skip looking up the heap tuple.
> >
> > The problem is that I can't figure out how be sure that the heap tuple
> > doesn't need to be looked at by _any_ backend. Right now, we update the
> > transaction commit flags in the heap tuple to prevent a pg_log lookup,
> > but that is not enough because some transactions may still see that heap
> > tuple as visible.
>
> If you are only marking those, that need not be visible anymore, can you not
> simply delete that key (slot) from the index ? I know vacuum then shows a count
> mismatch, but that could probably be accounted for.

I wasn't going to delete it, just add a flag to index scans know they
don't need to look at the heap table.

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