postgis not available for all postgres users

Question

When creating a new user on our Potgis enabled database I run into the strange issue that that new user cannot access the postgis extension while earlier created users can.

With my user account I get the following output:

mydb => SELECT postgis_version();
postgis_version
---------------------------------------
 2.3 USE_GEOS=1 USE_PROJ=1 USE_STATS=1
(1 row)

With the new user I get the following:

mydb => SELECT postgis_version()
mydb-> ;
ERROR:  function postgis_version() does not exist
LINE 1: SELECT postgis_version()
           ^
HINT:  No function matches the given name and argument types. You might need to add explicit type casts.

Also QGIS is giving me hint that postgis is not active:

2018-01-23T16:38:13 1   No PostGIS support in the database.

I am connecting to the exact same database. The user does have access to the public schema and to the geometry_columns table.

I am a bit lost here since according to my info Postgis is an extansion on the database level and it should be there for all users.

Answer 1

The PostGIS extension must be installed in a schema that must also be in the user search path.

You can check where it is installed with the command

select e.extname,n.* 
from pg_extension e, pg_namespace n 
where e.extnamespace = n.oid and e.extname='postgis';

And you can check if the schema where it is installed is in the user search path by issuing

show search_path;

If not, you can permanently add the path by altering the user.

ALTER USER username SET search_path TO "$user", public, postgis_schema;

As the previous command takes effect at the next login only, you can apply it immediately by applying

SET search_path TO "$user", public, postgis_schema;