I have to build a street network with PostGIS that will be used with pgRouting.
I have two tables:
the_network (182 lines): is a
MULTILINESTRINGtable. Having columns
buildings (104 lines): is a
The following code creates lines between buildings and the network. The 104 created lines are stored in
"buildings_to_network_lines_table" which is
SELECT ST_ShortestLine(a.geom, ST_Collect(b.geom)) AS geom, ST_Distance(a.geom, ST_Collect(b.geom)) AS shape_length INTO buildings_to_network_lines_table FROM buildings a, the_network b WHERE ST_Dwithin(a.geom, b.geom, 1000) GROUP BY by a.gid, a.geom;
Then I just want to create one table named the_network_full that contains all the lines of the_network and buildings_to_network_lines_table tables. I've tried to achieve this by a
SELECT ST_Union(a.geom, b.geom) AS the_network_full FROM the_network a, buildings_to_network_lines_table b;
The results look good but unfortunately the resulting
"the_network_full" table (type
GEOMETRY) contains 18'928 lines (
182*104) instead of
How can I merge these two tables into a new one?