Re: tweaking NTUP_PER_BUCKET - Mailing list pgsql-hackers

From Atri Sharma
Subject Re: tweaking NTUP_PER_BUCKET
Date
Msg-id CAOeZVic7oqWJUAwnQyZwR8WhjAmMK4jKTad7rhk=jSN-qEQfTw@mail.gmail.com
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In response to Re: tweaking NTUP_PER_BUCKET  (Stephen Frost <sfrost@snowman.net>)
Responses Re: tweaking NTUP_PER_BUCKET  (Greg Stark <stark@mit.edu>)
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On Thu, Jul 3, 2014 at 11:40 PM, Stephen Frost <sfrost@snowman.net> wrote:
Tomas,

* Tomas Vondra (tv@fuzzy.cz) wrote:
> However it's likely there are queries where this may not be the case,
> i.e. where rebuilding the hash table is not worth it. Let me know if you
> can construct such query (I wasn't).

Thanks for working on this!  I've been thinking on this for a while and
this seems like it may be a good approach.  Have you considered a bloom
filter?

IIRC, last time when we tried doing bloom filters, I was short of some real world useful hash functions that we could use for building the bloom filter.

If we are restarting experiments on this, I would be glad to assist.

Regards,

Atri

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