PostgreSQL

Login to PSQL

# [email protected]:~ #
su - postgres
# Last login: Tue Jan 01 12:00:00 MYT 2013 on pts/0
# -bash-4.2$
psql
# psql (9.6.8)
# Type "help" for help.
# 
# postgres=#

Login Error

# [email protected]:~ #
su - postgres psql
# Last login: Tue Jan 01 12:00:00 MYT 2013 on pts/0
# /bin/createuser: /bin/createuser: cannot execute binary file

Creating User

# [email protected]:~ #
su - postgres
# Last login: Tue Jan 01 12:00:00 MYT 2013 on pts/0
# -bash-4.2$
createuser root
# createuser: creation of new role failed: ERROR:  role "root" already exists

Creating DB

Until creating root database it's always show error could not change directory to "/root": Permission denied. To overcome this error we should need to create a root database. only for avoid error while login using root user.

# [email protected]:~ #
su - postgres
# Last login: Tue Jan 01 12:00:00 MYT 2013 on pts/0
# -bash-4.2$
createdb root

Similarly you can create a database as same as your frequently used OS User. In this case no need password to login. It will authenticated from OS. That's means you can login to your PostgreSQL user using OS Authentication.

Grant Privileges

# postgres=#
grant all privileges on database root to root;
# GRANT

# postgres=#
grant all privileges on database postgres to root;
# GRANT

Logout PSQL

# postgres=#
\q
# -bash-4.2$

Good to Know

-- psql
CREATE DATABASE chorke_init_pro;
CREATE USER chorke_init_pro WITH ENCRYPTED PASSWORD 'pa55w0rd';
GRANT ALL PRIVILEGES ON DATABASE chorke_init_pro TO chorke_init_pro;
-- \q

References

• PL/PgSQL Trigger
• PL/PgSQL Trigger
• SQL Create Procedure
• Creating user, database and adding access on PostgreSQL