Hi, I have created a table songs as follwoing:
CREATE TABLE songs ( song_id serial NOT NULL, title character varying(50) NOT NULL, composer varchar(50),
performer varchar(50), artist_id int4 not null, file_size int4, description text, extrInfo text,
highmd5 text, lowmd5 text, PRIMARY KEY (song_id), constraint fk_songs_art foreign key( artist_id) references
artist
);
I also created an other index on attribute title as:
create unique index title_idx on songs(title);
Then I vacuum analyzed my data base.
On command line I type :
explain select title from songs where song_id between 1 and 15 order by
song_id;
NOTICE: QUERY PLAN:
Sort (cost=1.70..1.70 rows=14 width=16) -> Seq Scan on songs (cost=0.00..1.44 rows=14 width=16)
EXPLAIN
One thing I don't uderstand why query planer is using a seq scan on my
table.
Why it is not using indexing defined. Thank you all for all your help.
Regards.
Najm
