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Strange indexing

From: Uros Gruber <uros(at)sir-mag(dot)com>
To: pgsql-general(at)postgresql(dot)org
Subject: Strange indexing
Date: 2002-04-29 16:34:04
Message-ID: (view raw, whole thread or download thread mbox)
Lists: pgsql-general

is this OK.

id int primary key,
name varchar(255),
parent varchar(32)

If i write

explain select * from test where id=1;

This is output of 1st table:
Index Scan using test_pkey on test  (cost=0.00..4.82 rows=1 width=183)

but the i create index on parent like this

create index tt on test (parent);

And when i execute query

explain select * from test where parent = '1';

Seq Scan on test  (cost=0.00..1.07 rows=1 width=17)

Why i there no index scan if i create index. I also run
vacuum on this table.

both queryes return only 1 row.

 Uros                          mailto:uros(at)sir-mag(dot)com


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