This post is useful if you have 2+ geo-referenced tables in PostGIS and are trying to visualize their rows on PgAdmin at the same time.
TL;DR
Just do a UNION query, make sure that the columns of each table match so the resulting union table make sense:
select id, geom from table1 where condition1 UNION select id, geom from table2 where condition2;
In detail
For the example below I’ve used the following data
- Montreal roads: http://donnees.ville.montreal.qc.ca/dataset/geobase
- Montreal downtown buildings: http://donnees.ville.montreal.qc.ca/dataset/batiment-2d, then select bâtiment 2D 2016 – Ville-Marie
Here is how they both look separately in PgAdmin
# Here I'm using ST_Force2D because the geometry is 3D for downtown_buildings # and PgAdmin does not support it yet for visualization select id, ST_Force2D(geom) from downtown_buildings;
# The 'roads' open data covers all Montreal, so I am limiting to downtown (Ville-Marie) select id, geom from roads where arr_gch='Ville-Marie';
Now we UNION them
select id, ST_Force2D(geom) from downtown_buildings UNION select id, geom from roads where arr_gch='Ville-Marie';
… and now you can see both the roads that lead to the Parc du Mont-Royal and the Kondiaronk Belvedere 🙂