sql - Non Equality Join on Hive -

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i trying emulate sql query on hive, grab data 2 tables do not have common field.

the 2 tables geometric (geohive) , 1 contains bunch of points (one each record) , other 1 grid (one cell each record). objective count how many points fit inside each cell.

enter image description here

the join condition between 2 tables geometric function itself. how in postgis:

select g.geom, count(t.geom) cnt    grid g, points t st_contains(g.geom,t.geom) group g.geom

hive not accept multiple select, have perform join. thought work:

select count(1) grid join points     st_contains(grid.geom,points.geom) group grid.geom;

, hive silently ignores condition:

"hive not support join conditions not equality conditions difficult express such conditions map/reduce job"

anyone has ideas of how refactor such query on hive?

i'll answer own question, state query attempt correct: failing other reasons, have nothing syntax.

select count(grid.geom) ptcnt grid join points st_contains(grid.geom,points.geom) group grid.geom;

this equivalent writing:

select count(grid.geom) ptcnt grid join points on(true) st_contains(grid.geom,points.geom) group grid.geom;

hive not in fact support non-equality joins, set join condition "true", , filter results on "where" clause.

apparently pretty standard behaviour spatial joins, can read here.


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