[postgis-users] update a table

[Bayu Kurniawan R]

i want update a table,

when i want to update, a wrote sql like :

UPDATE obj_cadangan_oil set working_area=(select block_name where
intersects(a.the_geom,b.the_geom) and b.the_geom ~ a.the_geom)
FROM map_field a, map_petroleum_contract_area b;

it's above query is right ???,
why it's take a long time to query

-- 
Bayu Kurniawan R
GIS Programmer
PT. Sigma Cipta Utama
Jl. Tekno I Blok B No:5,6,7
BSD City Tangerang 15314
Indonesia
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