Re: Why hash indexes suck

Added to TODO:

* Order heap pointers on hash index pages by hash value and ctid

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Zeugswetter Andreas SB SD wrote:
>
> > We could safely sort on the hash value, but I'm not sure how effective
> > that would be, considering that we're talking about values that already
> > hashed into the same bucket --- there's likely not to be very many
> > distinct hash values there.
>
> I think we can safely put that on the todo list.
> The existing hash algorithm is very good. So I would on the
> contrary beleive that only a few keys share a hash value per pagesized bucket.
> For the equal keys case it does not matter since we want all of the rows anyways.
> For the equal hash value case it would probably be best to sort by ctid.
>
> TODO ?: order heap pointers inside hash index pages by hash value and ctid
>
> Andreas
>
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