Re: Hash function for numeric (WIP) - Mailing list pgsql-patches

From Neil Conway
Subject Re: Hash function for numeric (WIP)
Date
Msg-id 1178650849.6034.17.camel@goldbach
Whole thread Raw
In response to Re: Hash function for numeric (WIP)  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Hash function for numeric (WIP)  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-patches
On Sun, 2007-06-05 at 21:30 -0400, Tom Lane wrote:
> It'd be a good idea if you repeat the previous number-of-collisions
> experiment on this code.

I repeated the same experiment, and got essentially the same number of
collisions (829 collisions on ~2 million randomly generated numerics,
with 273 duplicates). Since the modified hash still uses hash_any() and
really only differs when there are leading/trailing zeros, this is
consistent with what I'd expect.

Patch applied to HEAD.

-Neil



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