dbaston

-- Copyright Paul Ramsey, 2014
-- http://gis.stackexchange.com/questions/94203/how-to-group-connected-linestrings-in-postgis
 
drop table lines;
create table lines ( id integer primary key, geom geometry(linestring) );
insert into lines (id, geom) values ( 1, 'LINESTRING(0 0, 0 1)');
insert into lines (id, geom) values ( 2, 'LINESTRING(0 1, 1 1)');
insert into lines (id, geom) values ( 3, 'LINESTRING(1 1, 1 2)');
insert into lines (id, geom) values ( 4, 'LINESTRING(1 2, 2 2)');
insert into lines (id, geom) values ( 11, 'LINESTRING(10 10, 10 11)');