Re: BUG #1502: hash_seq_search might return removed entry

Thomas Hallgren wrote:
> Tom Lane wrote:
>
> >"Thomas" <thhal(at)mailblocks(dot)com> writes:
> >
> >
> >>The hash_seq_search keeps track of what element that it should return next
> >>in a HASH_SEQ_STATUS struct when it peruses a bucket. Removing that element
> >>from the table won't change anything since the struct remains unaffected. It
> >>still holds onto that element and hence, will return it on next iteration.
> >>
> >>
> >
> >This isn't a bug; it's the designed way for it to work. It's up to
> >callers to avoid causing a problem.
> >
> >
> This report origins from the hackers thread "SPI_finish and
> RegisterExprContextCallback" where you indicated that my report did not
> properly describe a problem. Since my report was correct and since you
> stated that "hash_seq_search() shouldn't return any already-dropped
> entries." I was led me to believe that it was *not* designed to do that.
>
> Anyway, the AtCommit_Portals doesn't avoid this problem and the end
> result for me is the same regardless of where the error is. I can't drop
> portals using a ExprContextCallback and I'd like to know the best way to
> fix it. I can contribute a patch but I want you to decide what needs to
> be fixed.

Does this need a C comment addition?

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