Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > My basic idea was to keep a status bit on each index entry telling it if
> > a previous backend looked at the heap and determined it was valid.
>
> Even if you could track the tuple's committed-good status reliably,
> that isn't enough under MVCC. The tuple might be committed good, and
> seen that way by some other backend that set the bit, and yet it's not
> supposed to be visible to your older transaction. Or the reverse at
> tuple deletion.
I mentioned that:
> (Oh, and you could only update the bit when all active transactions
> are newer than the creation transaction so we know they should all see
> it as visible.)
-- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610)
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