Problem with Bitmap Heap Scan

From: "Rushabh Lathia" <rushabh(dot)lathia(at)gmail(dot)com>
To: pgsql-hackers(at)postgresql(dot)org
Cc: heikki(at)enterprisedb(dot)com, rushabh(dot)lathia(at)enterprisedb(dot)com
Subject: Problem with Bitmap Heap Scan
Date: 2008-11-19 10:56:44
Message-ID: 460abcb10811190256pf9ce416ya398e6338d2e4476@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Simple select give wrong result when it uses the Bitmap Heap Scan path.

postgres=# CREATE OR REPLACE FUNCTION my_exec_im_test_func(i integer)
RETURNS integer AS $$
BEGIN
RETURN i + 1;
END;
$$ LANGUAGE plpgsql;
CREATE FUNCTION

postgres=# set enable_seqscan=off;
SET
postgres=# set enable_indexscan=off;
SET
postgres=# select proname from pg_proc where proname like 'my_pro1';
proname
----------------------
my_exec_im_test_proc
(1 row)

postgres=# explain select proname from pg_proc where proname like 'my_pro1';
QUERY
PLAN

--------------------------------------------------------------------------------
-------------
Bitmap Heap Scan on pg_proc (cost=4.26..8.27 rows=1 width=64)
Recheck Cond: (proname ~~ 'my_pro1'::text)
-> Bitmap Index Scan on pg_proc_proname_args_nsp_index (cost=0.00..4.26
row
s=1 width=0)
Index Cond: ((proname >= 'my'::name) AND (proname < 'mz'::name))
(4 rows)

--
Rushabh Lathia

www.EnterpriseDB.com

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Rushabh Lathia 2008-11-19 11:08:59 Re: Problem with Bitmap Heap Scan
Previous Message Heikki Linnakangas 2008-11-19 10:34:53 pgsql: Rethink the way FSM truncation works.