Database Fundamentals Coding Practice Challenges | CodeNivo

Question 1

14. Guided Practice

Accepted Answer

-- Task 1
CREATE DATABASE sql_practice;

Answer

-- Practice query for Creating Your First Database

Question 2

Guided Practice: Build a Library Relationship

Accepted Answer

-- Requirements:
-- 1. Create books with book_id as the primary key.
-- 2. Give each book a required title.
-- 3. Create book_copies with copy_id as the primary key.
-- 4. Require each copy to reference a valid book.
-- 5. Prevent deleting a book while copies still exist.

Answer

-- Practice query for Understanding Primary Keys and Foreign Keys

Question 3

19. Guided Practice

Accepted Answer

CREATE TABLE practice_products (
    product_id BIGINT
        GENERATED ALWAYS AS IDENTITY
        PRIMARY KEY,
    sku VARCHAR(50) NOT NULL UNIQUE,
    product_name VARCHAR(150) NOT NULL,
    price NUMERIC(10, 2) NOT NULL
        CHECK (price >= 0),
    stock_quantity INTEGER NOT NULL
        DEFAULT 0
        CHECK (stock_quantity >= 0),
    created_at TIMESTAMPTZ NOT NULL
        DEFAULT CURRENT_TIMESTAMP
);

Answer

-- Practice query for Creating Tables with CREATE TABLE

Question 4

15. Guided Practice

Accepted Answer

CREATE TABLE employees (
    employee_id INTEGER PRIMARY KEY,
    employee_name VARCHAR(100) NOT NULL,
    salary NUMERIC(10, 2) NOT NULL,
    joining_date DATE NOT NULL,
    is_active BOOLEAN NOT NULL DEFAULT TRUE
);

Answer

-- Practice query for Understanding Tables and Data Types

Database Fundamentals Problems