On 2020-Aug-11, Alvaro Herrera wrote:
> A much more troubling thought is what happens if the range is
> desummarized, then the index item is used for the summary of a different
> range. Then the index might end up returning corrupt results.
Actually, this is not a concern because the brin tuple's bt_blkno is
rechecked before returning it, and if it doesn't match what we're
searching, the loop is restarted. It becomes an infinite loop problem
if the revmap is pointing to a tuple that's labelled with a different
range's blkno. So I think my patch as posted is a sufficient fix for
this problem.
--
Álvaro Herrera https://www.2ndQuadrant.com/
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