PostgreSQL managed servers are expansive, why not just using your own VPS to add one?
This is a really short memo, the purpose is to have a PostgreSQL server running on a single computer as fast as possible to start dev things.
To allow connexions from any host on the internet
Edit the postgresql.conf file
sudo pico /etc/postgresql/13/main/postgresql.conf
# - Connection Settings - listen_addresses = '*' # what IP address(es) to listen on;
Add users authentification
sudo pico /etc/postgresql/13/main/pg_hba.conf
host all all 0.0.0.0/0 md5 host all all ::/0 md5
Create your first remotely allowed superuser
sudo -u postgres psql
postgres=# CREATE USER username WITH PASSWORD 'password' CREATEDB SUPERUSER CREATEROLE INHERIT LOGIN REPLICATION BYPASSRLS; CREATE ROLE postgres=# \q
sudo service postgresql restart
The best way to admin the database will be to remotely use pgAdmin you
could add users, change passwords and add databases on demand.
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