How To Install PostgreSQL on Ubuntu 21.04
PostgreSQL is a powerful, open source object-relational database system with over 30 years of active development that has earned it a strong reputation for reliability, feature robustness, and performance.
Install PostgreSQL on Ubuntu
Install PostgreSQL on Ubuntu by using following command.
sudo apt update
sudo apt install postgresql postgresql-contrib
Output:
[email protected]:~# apt install postgresql postgresql-contrib
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
postgresql-contrib is already the newest version (13+225ubuntu1).
The following packages were automatically installed and are no longer required:
libfile-find-rule-perl libnumber-compare-perl libtext-glob-perl
Use 'apt autoremove' to remove them.
Suggested packages:
postgresql-doc
The following NEW packages will be installed:
postgresql
PostgreSQL Roles and Databases
We'll switch to postgres account for this.
sudo -i -u postgres
you can access a PostgreSQL prompt using the psql utility.
psql
Ouput:
[email protected]:~$ psql
psql (13.2 (Ubuntu 13.2-1))
Type "help" for help.
postgres=#
To exit out of the PostgreSQL shell type.
\q
To Create PostgreSQL Role
sudo -u postgres createuser --interactive
Output:
Enter name of role to add: john
Shall the new role be a superuser? (y/n) y
To create PostgreSQL database
sudo -u postgres createdb john
To open a Postgres Prompt with the New Role.
sudo adduser john
To switch over and connect to the database.
sudo -u john psql
Output:
[email protected]:~# sudo -u john psql
could not change directory to "/root": Permission denied
psql (13.2 (Ubuntu 13.2-1))
Type "help" for help.
john=#
Once you logged in as john and check your current connection information.
\conninfo
Output:
john=# \conninfo
You are connected to database "john" as user "john" via socket in "/var/run/postgresql" at port "5432".
john=#