Re: Table Partitioning, Part 1 - Mailing list pgsql-hackers

From Hannu Krosing
Subject Re: Table Partitioning, Part 1
Date
Msg-id 1115732644.4779.83.camel@fuji.krosing.net
Whole thread Raw
In response to Re: Table Partitioning, Part 1  (Hannu Krosing <hannu@skype.net>)
Responses Re: Table Partitioning, Part 1  (Simon Riggs <simon@2ndquadrant.com>)
List pgsql-hackers
On T, 2005-05-10 at 16:31 +0300, Hannu Krosing wrote:
> On E, 2005-05-09 at 23:30 +0100, Simon Riggs wrote:

> There are 2 possibly expensive steps: 
> 
> 1. the conversion to "AND'ed list of simple clauses" (unknown
> complexity) 
> 
> 2. matching each of "simple" clauses in the and list with all others
> (should be N+(N-1)+(N-2)+..+(1) ~= 2N) complexity)

actually not 2N but (N * ((N-1)/2) , thus 3 clauses need 2+1=3 checks
and 11 clasues need (10+9+..+1) = 55 checks.

-- 
Hannu Krosing <hannu@skype.net>



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