i'm searching nearest ten neighbor points from a giving point.
When i use this query:
SELECT id, geom, ST_Distance(geography(geom), ST_GeographyFromText('SRID=4326;POINT(-0.22707 51.5444204)')) as distanceFROM carsORDER BY geom 'SRID=4326;POINT(-0.22707 51.5444204)'::geometryLIMIT 10;
i don't get the same result as when i use this query:
SELECT id, geom, ST_Distance(geography(geom), ST_GeographyFromText('POINT(-0.22707 51.5444204)')) as distanceFROM carsORDER BY distanceLIMIT 10;
Three of all the points returned are different. And when viewing it in qgis it looks like the best result is the last query. I need to use index-based KNN because of performance issues.
can you give some hint?
أكثر...
When i use this query:
SELECT id, geom, ST_Distance(geography(geom), ST_GeographyFromText('SRID=4326;POINT(-0.22707 51.5444204)')) as distanceFROM carsORDER BY geom 'SRID=4326;POINT(-0.22707 51.5444204)'::geometryLIMIT 10;
i don't get the same result as when i use this query:
SELECT id, geom, ST_Distance(geography(geom), ST_GeographyFromText('POINT(-0.22707 51.5444204)')) as distanceFROM carsORDER BY distanceLIMIT 10;
Three of all the points returned are different. And when viewing it in qgis it looks like the best result is the last query. I need to use index-based KNN because of performance issues.
can you give some hint?
أكثر...