DEFAULT values in SQL - Mini Project: Build & Apply

Using DEFAULT Values in SQL Tables

📖 Scenario: You are creating a simple database table to store information about books in a library. Some books may not have all details provided when they are added.

🎯 Goal: Create a table called Books with columns for BookID, Title, Author, and Available. Use a DEFAULT value for the Available column so that if no value is given, it is set to TRUE.

📋 What You'll Learn

Create a table named Books

Include columns BookID (integer), Title (text), Author (text), and Available (boolean)

Set the Available column to have a DEFAULT value of TRUE

Use standard SQL syntax

💡 Why This Matters

🌍 Real World

DEFAULT values are used in databases to automatically fill in missing data, making data entry easier and more reliable.

💼 Career

Knowing how to use DEFAULT values is important for database design and helps ensure data quality in real applications.

1

Create the Books table with basic columns

Write a SQL statement to create a table called Books with columns BookID as an integer, Title as text, and Author as text.

SQL

-- Your code here to create the Books table with BookID, Title, and Author columns

Need a hint?

Use CREATE TABLE Books (column_name data_type, ...); syntax.

2

Add the Available column with DEFAULT value

Modify the Books table creation statement to add a column called Available of type boolean with a DEFAULT value of TRUE.

SQL

CREATE TABLE Books (
    BookID INTEGER,
    Title TEXT,
    Author TEXT,
    -- Add Available column with DEFAULT TRUE here
);

Need a hint?

Add Available BOOLEAN DEFAULT TRUE as a new column.

3

Insert a book without specifying Available

Write a SQL INSERT statement to add a book with BookID 1, Title 'The Great Gatsby', and Author 'F. Scott Fitzgerald' without specifying the Available column.

SQL

-- Your INSERT statement here to add the book without Available column

Need a hint?

Use INSERT INTO Books (BookID, Title, Author) VALUES (...); without Available.

4

Insert a book specifying Available as FALSE

Write a SQL INSERT statement to add a book with BookID 2, Title '1984', Author 'George Orwell', and set Available explicitly to FALSE.

SQL

-- Your INSERT statement here to add the book with Available set to FALSE

Need a hint?

Include Available in the column list and set it to FALSE.