[postgis-users] Query using ST_Union and ST_Intersect

[Atul Kumar]

Hi All,

I am using ST_Union and ST_Intersect function to union and intersect geometry data of three table, but its taking huge time to execute.

Please  suggest me to optimal way to achieve those functionality.

My Query is :

select st_union(st_union(t1.geometry, t2.geometry), t3.geometry) geometry from TEMP_OUTPUTTREE_2 t1,TEMP_OUTPUTTREE2_4 t2, TEMP_OUTPUTTREE_5 t3

select st_intersection (st_intersection (t1.geometry, t2.geometry), t3.geometry) geometry from TEMP_OUTPUTTREE_2 t1,TEMP_OUTPUTTREE2_4 t2, TEMP_OUTPUTTREE_5 t3


Thanks
Atul Kumar

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