Re: Is the primary key constraint also an index?

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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Raymond O'Donnell, Director of Music, Galway Cathedral, Ireland
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