Re: Is the primary key constraint also an index? - Mailing list pgsql-general

From Raymond O'Donnell
Subject Re: Is the primary key constraint also an index?
Date
Msg-id 48A2AC4B.2050508@iol.ie
Whole thread Raw
In response to Is the primary key constraint also an index?  ("Tim Uckun" <timuckun@gmail.com>)
List pgsql-general
On 13/08/2008 03:18, Tim Uckun wrote:
> If I have a primary key constraint defined in the database do I also
> need to create an index on that field for fast lookup?

As I understand it, creating a primary key on a table also creates an
index automatically:

testdb=# create table test(f1 integer, f2 text);
CREATE TABLE
testdb=# alter table test add constraint test_pk primary key(f1);
NOTICE:  ALTER TABLE / ADD PRIMARY KEY will create implicit index
test_pk" for table "test"
ALTER TABLE


Ray.

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