Install postgreSQL on ubuntu

Summary:
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Install postgreSQL database on ubuntu system

Step 1:
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Update your system.

$ sudo apt-get update

Step 2:
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Install postgresql and associated packages

$ sudo apt-get install postgresql postgresql-contrib


Step 3:
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We need to stop Postgres server.

$ sudo service postgresql stop

Step 4:
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Navigate postgres user. Change PostgreSQL root user password.

$ sudo su postgres
$ psql


postgres=#  ALTER USER postgres WITH PASSWORD 'Passw0rd';
postgres=# \q


Step 5:
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We need to set the access permission  as trust to root user. The default access is md5. Open pg_hba.conf file

$ sudo subl /etc/postgresql/9.1/main/pg_hba.conf

Make sure the following commands

# Database administrative login by Unix domain socket
local   all             postgres                                trust

Step 6:
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We must restart the postgresql

$ sudo service postgresql restart