Most of our use-cases for the built-in json support in PostgreSQL is not to implement schemaless design storage, but instead to remold data.
One of the common cases we use json support is what we call UNPIVOTING data.
We demonstrated this in Postgres Vision 2018 presentation in slide 23.
This trick won't work in other relational databases that support JSON because
it also uses a long existing feature of PostgreSQL to be able to treat a row as a data field.
Unfortunately there are no slides of the pgRouting part, except the one that says PGRouting Live Demos because Leo will only do live demos. He has no fear of his demos not working.
Side note, if you are on windows and use the PostGIS bundle, all the extensions listed in the PostGIS box of the spatial extensions diagram, as well as the pointcloud, pgRouting, and ogr_fdw are included in the bundle.
The JSQuery extension is a PostgreSQL extension developed by Postgres Professional. You can get the source code and instructions for use at
https://github.com/postgrespro/jsquery. JSQuery is a fairly easy compile install if you are on a Nix system.
It provides more query functionality and additional index operator classes to support for JSONB than you get in built in PostgreSQL.
It is supported for PostgreSQL 9.4 and above.
We've built windows binaries for PostgreSQL 64-bit 9.4, 9.5, 9.6, and 10beta1. The 9.4 64-bit will only install on the EDB PostgreSQL 9.4 64-bit distribution.
The 9.5 and 9.6 are compatible with both PostgreSQL EDB and BigSQL distributions. The 10 has only been tested on BigSQL, but should work on EDB when it comes out. We should have 32-bit versions later and will link to those here.
If you do a lot of web-based GIS applications, a common desire is to allow a user to
draw out an area on the map and then do searches against that area and return back a FeatureCollection
where each feature is composed of a geometry and attributes about that feature. In the past the format
was GML or KML, but the world seems to be moving to prefer JSON/GeoJSON. Normally you'd throw
a mapping server that talks Web Feature Service
, do more or less with a webscripting glue, or use a Webservice
such as CartoDb that lets you pass along raw SQL.
In this article we'll demonstrate how to build GeoJSON feature collections that can be consumed by web mapping apps.
the built in JSON functions in PostgreSQL 9.2 and some PostGIS hugging.
Even if you
don't use PostGIS, we hope you'll come away with some techniques for working with
PostgreSQL extended types and also how to morph relational data into JSON buckets.