One of the things I'm most happy about with upcoming PostGIS 2.4.0, due out in about a week is that it is the first version to have almost complete translations into different languages. The Japanese, German, Portugese, and Korean translations are more than 80% complete with Japanese being 96%. You can download the html manuals from PostGIS docs page. Thwre are PDFs for non-Asian languages. Japanese and Korean languages I'm still having issue generating the pdfs.
When you install PostGIS with
CREATE EXTENSION postgis;, it also installs the accompanying help extracted from the manual in English format.
The comment generator we have in place is just as happy working with translated docs as it is with the English one so the in db help documents can also be generated in other languages. The help files are located:
Japanese, German, Portugese, and Korean
To use them, extract the files and from psql or pgAdmin, run the sql scripts. To experiment to see how this all looks I did the following.
CREATE EXTENSION postgis;
CREATE EXTENSION postgis_topology;
If you look in pgAdmin and navigate to topology schema, you'll see help that looks like:
If English is not your native language, you might want to install one of the other language packs.
I picked postgis_topology for this demonstration because it's self-contained and doesn't have a behemoth number of functions. You'll probably want to just use postgis_comments.sql and raster_comments.sql files.
First extracting the Japanese pack and running the topology_comments.sql
If you look in pgAdmin after script run and navigate to topology schema, refresh -> Functions -> Properties,
You'll see something like this:
The German one would look like
Note that while I'm showing this in pgAdmin, you can see the help in many tools including psql.