[postgis-tickets] [PostGIS] #3739: ST_Within Not using index

[PostGIS]

#3739: ST_Within Not using index
--------------------------+---------------------------
  Reporter:  postgispaul  |      Owner:  pramsey
      Type:  defect       |     Status:  new
  Priority:  medium       |  Milestone:  PostGIS 2.3.3
 Component:  postgis      |    Version:  2.3.x
Resolution:               |   Keywords:
--------------------------+---------------------------

Comment (by postgispaul):

 Total costs without enable_seqscan=false: 193474644

 with enable_seqscan=false:  475346571
 {{{
 Nested Loop  (cost=6230.89..475346571.95 rows=227104 width=271)
   Output: (ap.tags -> 'ISO3166-1'::text), s.admin_level, s.way, s.osm_id
   ->  Index Scan using polygon_iso3166_1_idx on public.planet_osm_polygon
 ap  (cost=0.28..1473.02 rows=1328 width=258)
         Output: ap.osm_id, ap.highway, ap.surface, ap.railway,
 ap.waterway, ap.tunnel, ap.bridge, ap.oneway, ap.access, ap.name,
 ap.z_order, ap.way_area, ap.area, ap.natural, ap.water, ap.admin_level,
 ap.boundary, ap.landuse, ap.amenity, ap.parking, ap.a (...)
         Index Cond: ((ap.tags -> 'ISO3166-1'::text) = 'KR'::text)
   ->  Bitmap Heap Scan on public.planet_osm_polygon s
 (cost=6230.62..357938.45 rows=171 width=239)
         Output: s.osm_id, s.highway, s.surface, s.railway, s.waterway,
 s.tunnel, s.bridge, s.oneway, s.access, s.name, s.z_order, s.way_area,
 s.area, s.natural, s.water, s.admin_level, s.boundary, s.landuse,
 s.amenity, s.parking, s.aeroway, s.military, s (...)
         Recheck Cond: (ap.way ~ s.way)
         Filter: ((s.admin_level ~ '^\d+$'::text) AND _st_contains(ap.way,
 s.way))
         ->  Bitmap Index Scan on planet_osm_polygon_index
 (cost=0.00..6230.57 rows=265635 width=0)
               Index Cond: (ap.way ~ s.way)
 }}}
 with extra ~ condition: 486830

--
Ticket URL: <https://trac.osgeo.org/postgis/ticket/3739#comment:23>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.