PostgreSQL is a database server. It is an object-relational database management system and it’s main purpose is to store data. PostgreSQL calls itself “The world’s most advanced open-source database”. It is a fact that MySQL andPostgreSQL are two most popular open-sourcerelation database management systems (RDMS). It is up to you to choose the one you like the most.

I have already written a post on how to “Install PostgreSQL 9.3 on CentOS 6” but installing PostgreSQL on CentOS 7 is not quite the same so i decided to write a new post “Install PostgreSQL 9.4 on CentOS 7”.

Let’s Install PostgreSQL 9.4 on CentOS 7!

1. Install PostgreSQL 9.4 Repository

Install the latest stable version of PostgreSQL 9.4 for CentOS 7 64bit. All available repositories can be found HERE.

[root@node-1 ~]# rpm -ivh http://yum.postgresql.org/9.4/redhat/rhel-7-x86_64/pgdg-centos94-9.4-1.noarch.rpm

2. Install PostgreSQL 9.4 Server and Dependencies

Install PostgreSQL 9.4 server from YUM repository installed in previous step. YUM will automatically resolve and install dependencies also.

[root@node-1 ~]# yum install postgresql94-server -y

3. Initialize PostgreSQL 9.4 Database

You need to initialize the PostgreSQL 9.4 database before you can successfully start it. This step differs from initializing the PostgreSQL database on CentOS version 6. You can’t run “service postgresql94 initdb” anymore, instead you must call the PostgreSQL 9.4 setup binary as follows:

[root@node-1 ~]# /usr/pgsql-9.4/bin/postgresql94-setup initdb
Initializing database ... OK

4. Start PostgreSQL 9.4 and Make it Start at Boot

You can find the PostgreSQL 9.4 service with the following command and also see that it is not enabled to start at boot:

[root@node-1 ~]# systemctl list-unit-files |grep postgres
postgresql-9.4.service disabled

Enable the PostgreSQL 9.4 service to start at boot:

[root@node-1 ~]# systemctl enable postgresql-9.4.service
ln -s '/usr/lib/systemd/system/postgresql-9.4.service' '/etc/systemd/system/multi-user.target.wants/postgresql-9.4.service'

..and start the PostgreSQL 9.4 service as follows:

[root@node-1 ~]# systemctl start postgresql-9.4.service

5. Confirm the Database is Running

You can confirm the database is running by viewing the process list:

[root@node-1 ~]# ps auxf |grep postgres
root 3091 0.0 0.1 112640 980 pts/0 S+ 11:41 0:00 _ grep --color=auto postgres
postgres 3042 0.0 1.9 337452 15200 ? S 11:40 0:00 /usr/pgsql-9.4/bin/postgres -D /var/lib/pgsql/9.4/data
postgres 3043 0.0 0.1 192600 1368 ? Ss 11:40 0:00 _ postgres: logger process 
postgres 3045 0.0 0.2 337452 1680 ? Ss 11:40 0:00 _ postgres: checkpointer process 
postgres 3046 0.0 0.3 337452 2480 ? Ss 11:40 0:00 _ postgres: writer process 
postgres 3047 0.0 0.2 337452 1688 ? Ss 11:40 0:00 _ postgres: wal writer process 
postgres 3048 0.0 0.3 337864 2608 ? Ss 11:40 0:00 _ postgres: autovacuum launcher process 
postgres 3049 0.0 0.2 192728 1744 ? Ss 11:40 0:00 _ postgres: stats collector process

.. and also by successfully connecting to the database as follows:

[root@node-1 ~]# su - postgres
Last login: Fri Jul 31 11:41:11 CEST 2015 on pts/0
-bash-4.2$ psql
psql (9.4.4)
Type "help" for help.

postgres=#

6. Edit Basic Configuration

Step 6 is still the same as with PostgreSQL 9.3 on CentOS 6. You can read the post HERE and jump to Step 6.