PostGIS ST_Intersects is slow and doesn't seem to use spatial index











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There are several threads about ST_Intersects being slow (like this one). Main advise is to use spatial index. Well I know that and created spatial index beforehand, but the query is slow nevertheless (takes about 2 hours to complete). Result of explain seems to show no sign of spatial index being used.



I want to mark which LineStrings in one table (~3M records) intersects the target Polygon in other (~30k records). The polygon is huge, but not that huge in comparison to the extent of entire dataset and I expect to catch about 100k records from the highway_only_motor table.



The query:



update highway_only_motor
set has_business_value = true
where st_intersects(geom, (select geom from admin_boundary where id = 10236))


Explain result:



QUERY PLAN                                                                                         |
---------------------------------------------------------------------------------------------------|
Update on highway_only_motor (cost=8.30..1241137.48 rows=1431564 width=1782) |
InitPlan 1 (returns $0) |
-> Index Scan using admin_boundary_pkey on admin_boundary (cost=0.29..8.30 rows=1 width=6768)|
Index Cond: (id = 10236) |
-> Seq Scan on highway_only_motor (cost=0.00..1241129.18 rows=1431564 width=1782) |
Filter: st_intersects(geom, $0) |


Tables:



CREATE TABLE public.highway_only_motor (
osm_id int8 NULL,
geom geometry NULL,
"name" text NULL,
highway text NULL,
"ref" text NULL,
oneway text NULL,
id serial NOT NULL,
city varchar(255) NULL,
state varchar(255) NULL,
country varchar(255) NULL,
has_business_value bool NOT NULL DEFAULT false,
CONSTRAINT highway_only_motor_pkey PRIMARY KEY (id)
);
CREATE INDEX highway_only_motor_geom_idx ON public.highway_only_motor USING gist (geom);

CREATE TABLE public.admin_boundary (
osm_id int8 NULL,
admin_level int4 NULL,
boundary text NULL,
"name" text NULL,
place text NULL,
population text NULL,
geom geometry NULL,
id serial NOT NULL,
CONSTRAINT admin_boundary_pkey PRIMARY KEY (id)
);
CREATE INDEX admin_boundary_geom_idx ON public.admin_boundary USING gist (geom);









share|improve this question






















  • have you tried rewriting the query to remove the sub-select?
    – Mike T
    18 hours ago










  • @MikeT you have a point - this is the root of the issue. With select replaced with straight WKT (a copy-paste) the query takes less than 30 seconds. Though I fail to properly rewrite the query to achieve the same result.
    – SS_Rebelious
    17 hours ago















up vote
3
down vote

favorite












There are several threads about ST_Intersects being slow (like this one). Main advise is to use spatial index. Well I know that and created spatial index beforehand, but the query is slow nevertheless (takes about 2 hours to complete). Result of explain seems to show no sign of spatial index being used.



I want to mark which LineStrings in one table (~3M records) intersects the target Polygon in other (~30k records). The polygon is huge, but not that huge in comparison to the extent of entire dataset and I expect to catch about 100k records from the highway_only_motor table.



The query:



update highway_only_motor
set has_business_value = true
where st_intersects(geom, (select geom from admin_boundary where id = 10236))


Explain result:



QUERY PLAN                                                                                         |
---------------------------------------------------------------------------------------------------|
Update on highway_only_motor (cost=8.30..1241137.48 rows=1431564 width=1782) |
InitPlan 1 (returns $0) |
-> Index Scan using admin_boundary_pkey on admin_boundary (cost=0.29..8.30 rows=1 width=6768)|
Index Cond: (id = 10236) |
-> Seq Scan on highway_only_motor (cost=0.00..1241129.18 rows=1431564 width=1782) |
Filter: st_intersects(geom, $0) |


Tables:



CREATE TABLE public.highway_only_motor (
osm_id int8 NULL,
geom geometry NULL,
"name" text NULL,
highway text NULL,
"ref" text NULL,
oneway text NULL,
id serial NOT NULL,
city varchar(255) NULL,
state varchar(255) NULL,
country varchar(255) NULL,
has_business_value bool NOT NULL DEFAULT false,
CONSTRAINT highway_only_motor_pkey PRIMARY KEY (id)
);
CREATE INDEX highway_only_motor_geom_idx ON public.highway_only_motor USING gist (geom);

CREATE TABLE public.admin_boundary (
osm_id int8 NULL,
admin_level int4 NULL,
boundary text NULL,
"name" text NULL,
place text NULL,
population text NULL,
geom geometry NULL,
id serial NOT NULL,
CONSTRAINT admin_boundary_pkey PRIMARY KEY (id)
);
CREATE INDEX admin_boundary_geom_idx ON public.admin_boundary USING gist (geom);









share|improve this question






















  • have you tried rewriting the query to remove the sub-select?
    – Mike T
    18 hours ago










  • @MikeT you have a point - this is the root of the issue. With select replaced with straight WKT (a copy-paste) the query takes less than 30 seconds. Though I fail to properly rewrite the query to achieve the same result.
    – SS_Rebelious
    17 hours ago













up vote
3
down vote

favorite









up vote
3
down vote

favorite











There are several threads about ST_Intersects being slow (like this one). Main advise is to use spatial index. Well I know that and created spatial index beforehand, but the query is slow nevertheless (takes about 2 hours to complete). Result of explain seems to show no sign of spatial index being used.



I want to mark which LineStrings in one table (~3M records) intersects the target Polygon in other (~30k records). The polygon is huge, but not that huge in comparison to the extent of entire dataset and I expect to catch about 100k records from the highway_only_motor table.



The query:



update highway_only_motor
set has_business_value = true
where st_intersects(geom, (select geom from admin_boundary where id = 10236))


Explain result:



QUERY PLAN                                                                                         |
---------------------------------------------------------------------------------------------------|
Update on highway_only_motor (cost=8.30..1241137.48 rows=1431564 width=1782) |
InitPlan 1 (returns $0) |
-> Index Scan using admin_boundary_pkey on admin_boundary (cost=0.29..8.30 rows=1 width=6768)|
Index Cond: (id = 10236) |
-> Seq Scan on highway_only_motor (cost=0.00..1241129.18 rows=1431564 width=1782) |
Filter: st_intersects(geom, $0) |


Tables:



CREATE TABLE public.highway_only_motor (
osm_id int8 NULL,
geom geometry NULL,
"name" text NULL,
highway text NULL,
"ref" text NULL,
oneway text NULL,
id serial NOT NULL,
city varchar(255) NULL,
state varchar(255) NULL,
country varchar(255) NULL,
has_business_value bool NOT NULL DEFAULT false,
CONSTRAINT highway_only_motor_pkey PRIMARY KEY (id)
);
CREATE INDEX highway_only_motor_geom_idx ON public.highway_only_motor USING gist (geom);

CREATE TABLE public.admin_boundary (
osm_id int8 NULL,
admin_level int4 NULL,
boundary text NULL,
"name" text NULL,
place text NULL,
population text NULL,
geom geometry NULL,
id serial NOT NULL,
CONSTRAINT admin_boundary_pkey PRIMARY KEY (id)
);
CREATE INDEX admin_boundary_geom_idx ON public.admin_boundary USING gist (geom);









share|improve this question













There are several threads about ST_Intersects being slow (like this one). Main advise is to use spatial index. Well I know that and created spatial index beforehand, but the query is slow nevertheless (takes about 2 hours to complete). Result of explain seems to show no sign of spatial index being used.



I want to mark which LineStrings in one table (~3M records) intersects the target Polygon in other (~30k records). The polygon is huge, but not that huge in comparison to the extent of entire dataset and I expect to catch about 100k records from the highway_only_motor table.



The query:



update highway_only_motor
set has_business_value = true
where st_intersects(geom, (select geom from admin_boundary where id = 10236))


Explain result:



QUERY PLAN                                                                                         |
---------------------------------------------------------------------------------------------------|
Update on highway_only_motor (cost=8.30..1241137.48 rows=1431564 width=1782) |
InitPlan 1 (returns $0) |
-> Index Scan using admin_boundary_pkey on admin_boundary (cost=0.29..8.30 rows=1 width=6768)|
Index Cond: (id = 10236) |
-> Seq Scan on highway_only_motor (cost=0.00..1241129.18 rows=1431564 width=1782) |
Filter: st_intersects(geom, $0) |


Tables:



CREATE TABLE public.highway_only_motor (
osm_id int8 NULL,
geom geometry NULL,
"name" text NULL,
highway text NULL,
"ref" text NULL,
oneway text NULL,
id serial NOT NULL,
city varchar(255) NULL,
state varchar(255) NULL,
country varchar(255) NULL,
has_business_value bool NOT NULL DEFAULT false,
CONSTRAINT highway_only_motor_pkey PRIMARY KEY (id)
);
CREATE INDEX highway_only_motor_geom_idx ON public.highway_only_motor USING gist (geom);

CREATE TABLE public.admin_boundary (
osm_id int8 NULL,
admin_level int4 NULL,
boundary text NULL,
"name" text NULL,
place text NULL,
population text NULL,
geom geometry NULL,
id serial NOT NULL,
CONSTRAINT admin_boundary_pkey PRIMARY KEY (id)
);
CREATE INDEX admin_boundary_geom_idx ON public.admin_boundary USING gist (geom);






postgis postgresql performance






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 18 hours ago









SS_Rebelious

4,62111852




4,62111852












  • have you tried rewriting the query to remove the sub-select?
    – Mike T
    18 hours ago










  • @MikeT you have a point - this is the root of the issue. With select replaced with straight WKT (a copy-paste) the query takes less than 30 seconds. Though I fail to properly rewrite the query to achieve the same result.
    – SS_Rebelious
    17 hours ago


















  • have you tried rewriting the query to remove the sub-select?
    – Mike T
    18 hours ago










  • @MikeT you have a point - this is the root of the issue. With select replaced with straight WKT (a copy-paste) the query takes less than 30 seconds. Though I fail to properly rewrite the query to achieve the same result.
    – SS_Rebelious
    17 hours ago
















have you tried rewriting the query to remove the sub-select?
– Mike T
18 hours ago




have you tried rewriting the query to remove the sub-select?
– Mike T
18 hours ago












@MikeT you have a point - this is the root of the issue. With select replaced with straight WKT (a copy-paste) the query takes less than 30 seconds. Though I fail to properly rewrite the query to achieve the same result.
– SS_Rebelious
17 hours ago




@MikeT you have a point - this is the root of the issue. With select replaced with straight WKT (a copy-paste) the query takes less than 30 seconds. Though I fail to properly rewrite the query to achieve the same result.
– SS_Rebelious
17 hours ago










1 Answer
1






active

oldest

votes

















up vote
5
down vote



accepted










Try



WITH
poly AS (
SELECT geom
FROM admin_boundary
WHERE id = <id>
)

UPDATE highway_only_motor AS a
SET has_business_value = true
FROM poly AS b
WHERE ST_Intersects(a.geom, b.geom);


With the pre-selection in the CTE, you should get similar performance as with a direct geometry reference in the ST_Intersects.






share|improve this answer

















  • 1




    This type of thing seems to come up once a week. I have been too immersed in watching my country of origin, the UK, slowly self destruct, from the safe distance of Spain, to have any time to answer questions.
    – John Powell
    16 hours ago






  • 2




    @JohnPowell SELECT ST_Intersection(a.civilisation, b.civilisation) FROM UK AS a, EU AS b; -> GEOMETRYCOLLECTION EMPTY. PostGIS politics extension.
    – ThingumaBob
    16 hours ago








  • 2




    Rotfl. Thank you my German friend for making me laugh. But really, based on current polls, it is SELECT ST_Area(ST_Intersection(a.civilisation, b.civilisation)) FROM UK AS a, EU AS b; result 0.53.
    – John Powell
    16 hours ago








  • 1




    @JohnPowell ...oh there's plenty of opportunity in PostGIS' function list =) those are the polls now? I really should follow the news some more. decision is tonight? ...well, last resort (and excuse my cynicism): it seems that Spain will stay loyal to the UNO migration pact...
    – ThingumaBob
    15 hours ago








  • 1




    Yup, whatukthinks.org/eu. It is incredible that it is only 53%. No, don't follow politics, it is massively depressing. Postgis and Python are much more enlightening. Yeah, Sanchez is a good PM, but, minority government. There are a lot of crazies here too, though nothing quite like the freakshow in London.
    – John Powell
    15 hours ago











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1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes








up vote
5
down vote



accepted










Try



WITH
poly AS (
SELECT geom
FROM admin_boundary
WHERE id = <id>
)

UPDATE highway_only_motor AS a
SET has_business_value = true
FROM poly AS b
WHERE ST_Intersects(a.geom, b.geom);


With the pre-selection in the CTE, you should get similar performance as with a direct geometry reference in the ST_Intersects.






share|improve this answer

















  • 1




    This type of thing seems to come up once a week. I have been too immersed in watching my country of origin, the UK, slowly self destruct, from the safe distance of Spain, to have any time to answer questions.
    – John Powell
    16 hours ago






  • 2




    @JohnPowell SELECT ST_Intersection(a.civilisation, b.civilisation) FROM UK AS a, EU AS b; -> GEOMETRYCOLLECTION EMPTY. PostGIS politics extension.
    – ThingumaBob
    16 hours ago








  • 2




    Rotfl. Thank you my German friend for making me laugh. But really, based on current polls, it is SELECT ST_Area(ST_Intersection(a.civilisation, b.civilisation)) FROM UK AS a, EU AS b; result 0.53.
    – John Powell
    16 hours ago








  • 1




    @JohnPowell ...oh there's plenty of opportunity in PostGIS' function list =) those are the polls now? I really should follow the news some more. decision is tonight? ...well, last resort (and excuse my cynicism): it seems that Spain will stay loyal to the UNO migration pact...
    – ThingumaBob
    15 hours ago








  • 1




    Yup, whatukthinks.org/eu. It is incredible that it is only 53%. No, don't follow politics, it is massively depressing. Postgis and Python are much more enlightening. Yeah, Sanchez is a good PM, but, minority government. There are a lot of crazies here too, though nothing quite like the freakshow in London.
    – John Powell
    15 hours ago















up vote
5
down vote



accepted










Try



WITH
poly AS (
SELECT geom
FROM admin_boundary
WHERE id = <id>
)

UPDATE highway_only_motor AS a
SET has_business_value = true
FROM poly AS b
WHERE ST_Intersects(a.geom, b.geom);


With the pre-selection in the CTE, you should get similar performance as with a direct geometry reference in the ST_Intersects.






share|improve this answer

















  • 1




    This type of thing seems to come up once a week. I have been too immersed in watching my country of origin, the UK, slowly self destruct, from the safe distance of Spain, to have any time to answer questions.
    – John Powell
    16 hours ago






  • 2




    @JohnPowell SELECT ST_Intersection(a.civilisation, b.civilisation) FROM UK AS a, EU AS b; -> GEOMETRYCOLLECTION EMPTY. PostGIS politics extension.
    – ThingumaBob
    16 hours ago








  • 2




    Rotfl. Thank you my German friend for making me laugh. But really, based on current polls, it is SELECT ST_Area(ST_Intersection(a.civilisation, b.civilisation)) FROM UK AS a, EU AS b; result 0.53.
    – John Powell
    16 hours ago








  • 1




    @JohnPowell ...oh there's plenty of opportunity in PostGIS' function list =) those are the polls now? I really should follow the news some more. decision is tonight? ...well, last resort (and excuse my cynicism): it seems that Spain will stay loyal to the UNO migration pact...
    – ThingumaBob
    15 hours ago








  • 1




    Yup, whatukthinks.org/eu. It is incredible that it is only 53%. No, don't follow politics, it is massively depressing. Postgis and Python are much more enlightening. Yeah, Sanchez is a good PM, but, minority government. There are a lot of crazies here too, though nothing quite like the freakshow in London.
    – John Powell
    15 hours ago













up vote
5
down vote



accepted







up vote
5
down vote



accepted






Try



WITH
poly AS (
SELECT geom
FROM admin_boundary
WHERE id = <id>
)

UPDATE highway_only_motor AS a
SET has_business_value = true
FROM poly AS b
WHERE ST_Intersects(a.geom, b.geom);


With the pre-selection in the CTE, you should get similar performance as with a direct geometry reference in the ST_Intersects.






share|improve this answer












Try



WITH
poly AS (
SELECT geom
FROM admin_boundary
WHERE id = <id>
)

UPDATE highway_only_motor AS a
SET has_business_value = true
FROM poly AS b
WHERE ST_Intersects(a.geom, b.geom);


With the pre-selection in the CTE, you should get similar performance as with a direct geometry reference in the ST_Intersects.







share|improve this answer












share|improve this answer



share|improve this answer










answered 16 hours ago









ThingumaBob

5,4681222




5,4681222








  • 1




    This type of thing seems to come up once a week. I have been too immersed in watching my country of origin, the UK, slowly self destruct, from the safe distance of Spain, to have any time to answer questions.
    – John Powell
    16 hours ago






  • 2




    @JohnPowell SELECT ST_Intersection(a.civilisation, b.civilisation) FROM UK AS a, EU AS b; -> GEOMETRYCOLLECTION EMPTY. PostGIS politics extension.
    – ThingumaBob
    16 hours ago








  • 2




    Rotfl. Thank you my German friend for making me laugh. But really, based on current polls, it is SELECT ST_Area(ST_Intersection(a.civilisation, b.civilisation)) FROM UK AS a, EU AS b; result 0.53.
    – John Powell
    16 hours ago








  • 1




    @JohnPowell ...oh there's plenty of opportunity in PostGIS' function list =) those are the polls now? I really should follow the news some more. decision is tonight? ...well, last resort (and excuse my cynicism): it seems that Spain will stay loyal to the UNO migration pact...
    – ThingumaBob
    15 hours ago








  • 1




    Yup, whatukthinks.org/eu. It is incredible that it is only 53%. No, don't follow politics, it is massively depressing. Postgis and Python are much more enlightening. Yeah, Sanchez is a good PM, but, minority government. There are a lot of crazies here too, though nothing quite like the freakshow in London.
    – John Powell
    15 hours ago














  • 1




    This type of thing seems to come up once a week. I have been too immersed in watching my country of origin, the UK, slowly self destruct, from the safe distance of Spain, to have any time to answer questions.
    – John Powell
    16 hours ago






  • 2




    @JohnPowell SELECT ST_Intersection(a.civilisation, b.civilisation) FROM UK AS a, EU AS b; -> GEOMETRYCOLLECTION EMPTY. PostGIS politics extension.
    – ThingumaBob
    16 hours ago








  • 2




    Rotfl. Thank you my German friend for making me laugh. But really, based on current polls, it is SELECT ST_Area(ST_Intersection(a.civilisation, b.civilisation)) FROM UK AS a, EU AS b; result 0.53.
    – John Powell
    16 hours ago








  • 1




    @JohnPowell ...oh there's plenty of opportunity in PostGIS' function list =) those are the polls now? I really should follow the news some more. decision is tonight? ...well, last resort (and excuse my cynicism): it seems that Spain will stay loyal to the UNO migration pact...
    – ThingumaBob
    15 hours ago








  • 1




    Yup, whatukthinks.org/eu. It is incredible that it is only 53%. No, don't follow politics, it is massively depressing. Postgis and Python are much more enlightening. Yeah, Sanchez is a good PM, but, minority government. There are a lot of crazies here too, though nothing quite like the freakshow in London.
    – John Powell
    15 hours ago








1




1




This type of thing seems to come up once a week. I have been too immersed in watching my country of origin, the UK, slowly self destruct, from the safe distance of Spain, to have any time to answer questions.
– John Powell
16 hours ago




This type of thing seems to come up once a week. I have been too immersed in watching my country of origin, the UK, slowly self destruct, from the safe distance of Spain, to have any time to answer questions.
– John Powell
16 hours ago




2




2




@JohnPowell SELECT ST_Intersection(a.civilisation, b.civilisation) FROM UK AS a, EU AS b; -> GEOMETRYCOLLECTION EMPTY. PostGIS politics extension.
– ThingumaBob
16 hours ago






@JohnPowell SELECT ST_Intersection(a.civilisation, b.civilisation) FROM UK AS a, EU AS b; -> GEOMETRYCOLLECTION EMPTY. PostGIS politics extension.
– ThingumaBob
16 hours ago






2




2




Rotfl. Thank you my German friend for making me laugh. But really, based on current polls, it is SELECT ST_Area(ST_Intersection(a.civilisation, b.civilisation)) FROM UK AS a, EU AS b; result 0.53.
– John Powell
16 hours ago






Rotfl. Thank you my German friend for making me laugh. But really, based on current polls, it is SELECT ST_Area(ST_Intersection(a.civilisation, b.civilisation)) FROM UK AS a, EU AS b; result 0.53.
– John Powell
16 hours ago






1




1




@JohnPowell ...oh there's plenty of opportunity in PostGIS' function list =) those are the polls now? I really should follow the news some more. decision is tonight? ...well, last resort (and excuse my cynicism): it seems that Spain will stay loyal to the UNO migration pact...
– ThingumaBob
15 hours ago






@JohnPowell ...oh there's plenty of opportunity in PostGIS' function list =) those are the polls now? I really should follow the news some more. decision is tonight? ...well, last resort (and excuse my cynicism): it seems that Spain will stay loyal to the UNO migration pact...
– ThingumaBob
15 hours ago






1




1




Yup, whatukthinks.org/eu. It is incredible that it is only 53%. No, don't follow politics, it is massively depressing. Postgis and Python are much more enlightening. Yeah, Sanchez is a good PM, but, minority government. There are a lot of crazies here too, though nothing quite like the freakshow in London.
– John Powell
15 hours ago




Yup, whatukthinks.org/eu. It is incredible that it is only 53%. No, don't follow politics, it is massively depressing. Postgis and Python are much more enlightening. Yeah, Sanchez is a good PM, but, minority government. There are a lot of crazies here too, though nothing quite like the freakshow in London.
– John Powell
15 hours ago


















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