To install PostgreSQL on Ubuntu, run

apt install postgresql

To check status, run

root@ip-172-31-26-32:~# systemctl status postgresql
● postgresql.service - PostgreSQL RDBMS
   Loaded: loaded (/lib/systemd/system/postgresql.service; enabled; vendor preset: enabled)
   Active: active (exited) since Fri 2017-02-17 20:48:16 UTC; 3min 19s ago
 Main PID: 1375 (code=exited, status=0/SUCCESS)
   CGroup: /system.slice/postgresql.service

Feb 17 20:48:16 ip-172-31-26-32 systemd[1]: Starting PostgreSQL RDBMS...
Feb 17 20:48:16 ip-172-31-26-32 systemd[1]: Started PostgreSQL RDBMS.
Feb 17 20:48:21 ip-172-31-26-32 systemd[1]: Started PostgreSQL RDBMS.
root@ip-172-31-26-32:~# 

Using PostgreSQL

root@ip-172-31-26-32:~# su - postgres
postgres@ip-172-31-26-32:~$ psql
psql (9.5.5)
Type "help" for help.

postgres=# 

Back to PostgreSQL