Ubuntu 16.04.2 に PostgreSQL 9.6 をインストール

PostgreSQL – Linux downloads (Ubuntu)
https://www.postgresql.org/download/linux/ubuntu/

sudo add-apt-repository "deb http://apt.postgresql.org/pub/repos/apt/ xenial-pgdg main"
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo apt-get update
sudo apt-get -y install postgresql-9.6

ログ

Success. You can now start the database server using:

    /usr/lib/postgresql/9.6/bin/pg_ctl -D /var/lib/postgresql/9.6/main -l logfile start

Ver Cluster Port Status Owner    Data directory               Log file
9.6 main    5432 down   postgres /var/lib/postgresql/9.6/main /var/log/postgresql/postgresql-9.6-main.log
update-alternatives: using /usr/share/postgresql/9.6/man/man1/postmaster.1.gz to provide /usr/share/man/man1/postmaster.1.gz (postmaster.1.gz) in auto mode
Setting up postgresql-contrib-9.6 (9.6.3-1.pgdg16.04+1) ...
Setting up sysstat (11.2.0-1ubuntu0.1) ...

Creating config file /etc/default/sysstat with new version
update-alternatives: using /usr/bin/sar.sysstat to provide /usr/bin/sar (sar) in auto mode
Processing triggers for libc-bin (2.23-0ubuntu5) ...
Processing triggers for systemd (229-4ubuntu16) ...
Processing triggers for ureadahead (0.100.0-19) ...

How to install PostgreSQL 9.6 on any Ubuntu version
How do I install PostgreSQL 9.6 on any Ubuntu version?
How do I install PostgreSQL 9.6 on any Ubuntu version since it doesn't come by default with the most recent version?

Ubuntu Xenial (16.04) comes with PostgreSQ...
askubuntu.com

postgres という名前の Linux ユーザーが自動作成されます。ただし、パスワードが設定されていないので設定します。

sudo passwd postgres

postgres ユーザーにスイッチし、psql で何か適当なデータベースとロールを作成してみます。

su - postgres
psql
CREATE ROLE user LOGIN CREATEDB PASSWORD 'user1234';
CREATE DATABASE spring_boot_gcp OWNER user;