db_1 | performing post-bootstrap initialization ... sh: locale: not found
db_1 | 2018-09-21 08:09:09.513 UTC [28] WARNING: no usable system locales were found
db_1 | ok
db_1 | syncing data to disk ...
FROM postgres:11-alpine
COPY ./sql/init.ql /docker-entrypoint-initdb.d/init.sql
RUN docker-entrypoint.sh
FROM postgres:11-alpine
COPY --from=0 /var/lib/postgresql/data /var/lib/postgresql/data
Alpine is based on musl which doesn't have locales.
Going to close as there's nothing we could change in the image to remedy this
https://github.com/docker-library/docs/tree/master/postgres#postgresversion-alpine
The main caveat to note is that it does use musl libc instead of glibc and friends, so certain software might run into issues depending on the depth of their libc requirements.
Its possible to add locales now as per this example.
This is my Postgres-Alpine locale:

This is my Postgres db settings:

Why my monetary values aren't in pt_BR format?

The amounts should be as: R$ 100,00
What remains to be done for this to work?
Most helpful comment
Its possible to add locales now as per this example.