psql command-line tool basics in PostgreSQL - Mini Project: Build & Apply

psql Command-Line Tool Basics

📖 Scenario: You are a new database administrator for a small company. You need to learn how to use the psql command-line tool to interact with a PostgreSQL database. This will help you manage data and run queries efficiently.

🎯 Goal: Learn the basic commands to connect to a PostgreSQL database using psql, list tables, describe table structure, and run simple SQL queries.

📋 What You'll Learn

Connect to a PostgreSQL database using psql with a database name

List all tables in the connected database using a psql command

Describe the structure of a specific table using a psql command

Run a simple SQL query to select data from a table

💡 Why This Matters

🌍 Real World

Database administrators and developers use psql to manage PostgreSQL databases efficiently from the command line.

💼 Career

Knowing psql commands is essential for database management, troubleshooting, and running queries in many IT and data roles.

1

Connect to the PostgreSQL database

Use the psql command to connect to a PostgreSQL database named company_db. Write the exact command to connect.

PostgreSQL

# Type the command to connect to the database named company_db
# Your code here

Need a hint?

Use psql followed by the database name to connect.

2

List all tables in the database

After connecting to company_db, use the psql meta-command to list all tables in the current database. Write the exact command starting with a backslash.

PostgreSQL

psql company_db
# Type the command to list all tables
# Your code here

Need a hint?

Use \dt to list tables in psql.

3

Describe the structure of a table

Use the psql meta-command to describe the structure of the table named employees. Write the exact command starting with a backslash.

PostgreSQL

\dt
# Type the command to describe the employees table
# Your code here

Need a hint?

Use \d employees to see the table structure.

4

Run a simple SQL query

Write a SQL query to select all columns from the employees table. End the query with a semicolon.

PostgreSQL

\dt
\d employees
# Write a SQL query to select all columns from employees
# Your code here

Need a hint?

Use SELECT * FROM employees; to get all data from the table.