Re: Multicolum index and primary key - Mailing list pgsql-sql

From Peter Eisentraut
Subject Re: Multicolum index and primary key
Date
Msg-id Pine.LNX.4.44.0311171713460.12502-100000@peter.localdomain
Whole thread Raw
In response to Multicolum index and primary key  (Michele Bendazzoli <mickymouse@mickymouse.it>)
Responses Re: Multicolum index and primary key  (Michele Bendazzoli <mickymouse@mickymouse.it>)
List pgsql-sql
Michele Bendazzoli writes:

> ALTER TABLE public.table1
>   ADD CONSTRAINT table1_pkey PRIMARY KEY(a, b, c);
>
> are the indexes over (a) and (a, b) redundant (and so useless)?

Exactly.

> p.s. I know, I'll have to begin to use the explain command ...
> I promise I'll do it ;-)

You could also have read the documentation about multicolumn indexes,
because it contains exactly this example.

-- 
Peter Eisentraut   peter_e@gmx.net



pgsql-sql by date:

Previous
From: Michele Bendazzoli
Date:
Subject: Multicolum index and primary key
Next
From: Tomasz Myrta
Date:
Subject: Re: Multicolum index and primary key