CREATE USER is an alias for CREATE ROLE. The only difference is that when the CREATE USER command is used , LOGIN is assumed by default, whereas NOLOGIN is assumed when the CREATE ROLE command is used
ALTER TABLE changes the definition of an existing table.
Dump method is to generate a file with SQL commands that, when fed back to the server, will recreate the database in the same state as it was at the time of the dump. PostgreSQL provides the utility program pg_dump for this purpose.
CREATE DATABASE creates a new PostgreSQL database.To create a database, you must be a superuser or have the special CREATEDB privilege.
There can be Ident authentication errors in PostgreSQL while connecting with psycopg2 module, below is the samsple snapshot of the error.These errors can be resolved with below steps.
CREATE DATABASE creates a new PostgreSQL database.To create a database, you must be a superuser or have the special CREATEDB privilege.
INSERT command inserts new rows into a table. for this tutorial we already have db created with with name "test_db". "test_db" is having table with name testtable.