Index not used in join.. (example included)

Hi,

I don't understand why my query doesn't use the index on the name column:

CREATE TABLE celeb (
id serial,
name varchar(255) NOT NULL,
PRIMARY KEY (id)
);

create index celeb_name_index on celeb (name);
INSERT INTO celeb (name) values ('Cameron Diaz');
INSERT INTO celeb (name) values ('Angelina Jolie');
INSERT INTO celeb (name) values ('Reese Witherspoon');

CREATE TABLE detail (
id serial,
name varchar(255) NOT NULL,
award date,
PRIMARY KEY (id)
);

create index detail_name_index on detail (name);
INSERT INTO detail (name, award) values ('Cameron Diaz', '2009-01-01');
INSERT INTO detail (name, award) values ('Cameron Diaz', '2009-02-01');
INSERT INTO detail (name, award) values ('Cameron Diaz', '2009-03-01');
INSERT INTO detail (name, award) values ('Angelina Jolie', '2009-01-01');
INSERT INTO detail (name, award) values ('Angelina Jolie', '2009-02-01');
INSERT INTO detail (name, award) values ('Angelina Jolie', '2009-03-01');
INSERT INTO detail (name, award) values ('Angelina Jolie', '2009-04-01');
INSERT INTO detail (name, award) values ('Reese Witherspoon', '2009-01-01');
INSERT INTO detail (name, award) values ('Reese Witherspoon', '2009-02-01');
INSERT INTO detail (name, award) values ('Reese Witherspoon', '2009-03-01');
INSERT INTO detail (name, award) values ('Reese Witherspoon', '2009-04-01');
INSERT INTO detail (name, award) values ('Reese Witherspoon', '2009-05-01');

stium=# explain select * from celeb left join detail on detail.name = celeb.name;
QUERY PLAN
-----------------------------------------------------------------------
Hash Left Join (cost=11.75..25.30 rows=140 width=1044)
Hash Cond: (("outer".name)::text = ("inner".name)::text)
-> Seq Scan on celeb (cost=0.00..11.40 rows=140 width=520)
-> Hash (cost=11.40..11.40 rows=140 width=524)
-> Seq Scan on detail (cost=0.00..11.40 rows=140 width=524)
(5 rows)

Now, why does it use sequential scans?? I don't get it. It also does this
on a very large table which is ANALYZE'd.

Thanks,
Ron

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