SQL Challenge: One Concept Every Day

Day-1

Creating Databases and Tables in PostgreSQL

How to Create a Database in PostgreSQL

There are two common ways to create a PostgreSQL database:

• Using Terminal / psql [Linux]
• Using pgAdmin

Create a Database Using Terminal

sudo -i -u postgres

sudo (superUser Do) → run a command with administrator privileges
-i → start a login shell
-u → specify which user to switch to
postgres → PostgreSQL system user

CREATE DATABASE company;

we can check the version with the SQL statement ,

SELECT version();

note :
\l - to Check databases

\c company - to connect Database

\d - It shows the tables, views, sequences, etc.
in the current database

In pgAdmin4

PostgreSQL Create Table

CREATE TABLE employee(
  id INT,
  name VARCHAR(25),
  role VARCHAR(25),
  exp INT
);

PostgreSQL Insert Data

1. Insert one row

INSERT INTO employee (id, name, role, experience)
VALUES (1, 'vidhya', 'Full Stack Developer', 1);

1. Insert multiple rows

INSERT INTO employee (id, name, role, experience)
VALUES
(1, 'Vidhya', 'Developer', 2),
(2, 'Arav', 'Tester', 3),
(3, 'Amutha', 'Manager', 5),
(4, 'Prem', 'Developer', 4);

Display Table

To check the result we can display the table with this SQL statement:

SELECT * FROM employee;

That's it for Day 1. To be continued.....