Kevin Grittner <kgrittn(at)ymail(dot)com> writes:
> Are we talking about the probe for the end (or beginning) of an
> index? If so, should we even care about visibility of the row
> related to the most extreme index entry? Should we even go to the
> heap during the plan phase?
Consider the case where some transaction inserted a wildly out-of-range
value, then rolled back. If we don't check validity of the heap row,
we'd be using that silly endpoint value for planning purposes ---
indefinitely. That's not an improvement over the situation that the
probe is meant to fix.
regards, tom lane