[postgis-users] Split multiple overlapping polygons to polygons that do not overlap.

[Moen, Paul T.]

I have a set of polygons.

INSERT INTO test(gid,the_geom) VALUES (1,st_geomfromtext('MULTIPOLYGON 
(((1 5,1 9,5 9,5 5,1 5)))',2266));
INSERT INTO test(gid,the_geom) VALUES (2,st_geomfromtext('MULTIPOLYGON 
(((4 2,4 6,8 6,8 2,4 2)))',2266));
INSERT INTO test(gid,the_geom) VALUES (3,st_geomfromtext('MULTIPOLYGON 
(((4 3,4 6,7 6,7 3,4 3)))',2266));
INSERT INTO test(gid,the_geom) VALUES (4,st_geomfromtext('MULTIPOLYGON 
(((4 5,4 8,7 8,7 5,4 5)))',2266));
INSERT INTO test(gid,the_geom) VALUES (5,st_geomfromtext('MULTIPOLYGON 
(((2 3,2 6,5 6,5 3,2 3)))',2266));
They look like the image below with the transparency set so the  
overlaps are visible.

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