From: | "" <agattik(at)gmail(dot)com> |
---|---|
To: | pgsql-bugs(at)postgresql(dot)org |
Subject: | BUG #2196: Useless RECHECK on RTREE index |
Date: | 2006-01-23 05:44:04 |
Message-ID: | 20060123054404.60237F0AC7@svr2.postgresql.org |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-bugs |
The following bug has been logged online:
Bug reference: 2196
Logged by:
Email address: agattik(at)gmail(dot)com
PostgreSQL version: 8.1.2
Operating system: alphaev68-dec-osf5.1a
Description: Useless RECHECK on RTREE index
Details:
create table tpoints (x int, y int);
CREATE INDEX i_tpoints ON tpoints USING RTREE (box(point(x,y),
point(x,y)));
explain select * from tpoints where box '((0,0),(1,1))' && box(point(x,y),
point(x,y));
QUERY PLAN
----------------------------------------------------------------------------
----------------------------------------------------------------------------
---
Bitmap Heap Scan on tpoints (cost=1.05..10.46 rows=10 width=8)
Recheck Cond: ('(1,1),(0,0)'::box && box(point((x)::double precision,
(y)::double precision), point((x)::double precision, (y)::double
precision)))
-> Bitmap Index Scan on i_tpoints (cost=0.00..1.05 rows=10 width=0)
Index Cond: ('(1,1),(0,0)'::box && box(point((x)::double precision,
(y)::double precision), point((x)::double precision, (y)::double
precision)))
(4 rows)
The RECHECK is necessary in case of polygons, but useless in case of box
overlap.
pg_amop.amopreqcheck is correctly set to false, but the planner seems to
ignore that.
select pg_amop.* from pg_amop join pg_opclass c ON (amopclaid=c.oid) join
pg_operator op ON (amopopr=op.oid) where opcname='box_ops' and
oprname='&&';
amopclaid | amopsubtype | amopstrategy | amopreqcheck | amopopr
-----------+-------------+--------------+--------------+---------
425 | 0 | 3 | f | 500
2593 | 0 | 3 | f | 500
(2 rows)
From | Date | Subject | |
---|---|---|---|
Next Message | Milen A. Radev | 2006-01-23 09:14:03 | Re: BUG #2195: log_min_messages crash server when in DEBUG3 to 5 |
Previous Message | Andras Got | 2006-01-22 13:30:38 | Re: BUG #2193: INITCAP and LOWER/UPPER string conversion error |