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peterdesmet/belgian-lambert-to-wgs84.sql

Last active August 29, 2015 14:07
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Transform Belgian Lambert to WGS84 in PostgreSQL
Raw
belgian-lambert-to-wgs84.sql
-- SetSRID defines the datum. Use 31370, not 31300 for Belgian Lambert 72
SELECT
*,
ST_Transform(ST_SetSRID(ST_MakePoint(x,y),31370),4326) as geom_from_lambert,
ST_Y(ST_Transform(ST_SetSRID(ST_MakePoint(x,y),31370),4326)) as latitude_from_lambert,
ST_X(ST_Transform(ST_SetSRID(ST_MakePoint(x,y),31370),4326)) as longitude_from_lambert
FROM table_name
Raw
update_statement.sql
UPDATE table_name SET latitude_from_lambert = round(ST_Y(ST_Transform(ST_SetSRID(ST_MakePoint(x,y),31370),4326))::numeric,7);
UPDATE table_name SET longitude_from_lambert = round(ST_X(ST_Transform(ST_SetSRID(ST_MakePoint(x,y),31370),4326))::numeric,7);
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geom_from_lambert seems to be interpreted as a string, not sure what function is required to make this a geometry.

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