INSERT INTO single row in MySQL - Mini Project: Build & Apply

Insert a Single Row into a MySQL Table

📖 Scenario: You are managing a small bookstore database. You want to add a new book to the books table.

🎯 Goal: Learn how to insert a single row into a MySQL table using the INSERT INTO statement.

📋 What You'll Learn

Create a table called books with columns id, title, and author

Add a new book entry with specific values using INSERT INTO

Use exact column names and values as instructed

💡 Why This Matters

🌍 Real World

In real life, inserting data into a database is how you add new records like books, customers, or orders.

💼 Career

Database administrators and developers frequently use INSERT statements to add data to databases in applications.

1

Create the books table

Write a SQL statement to create a table called books with three columns: id as an integer primary key, title as a VARCHAR(100), and author as a VARCHAR(100).

MySQL

-- Your code here to create the books table

Hint

Use CREATE TABLE books (id INT PRIMARY KEY, title VARCHAR(100), author VARCHAR(100));

2

Prepare to insert a new book

Write a SQL statement to insert a new row into the books table with columns id, title, and author. Use the values 1 for id, 'The Great Gatsby' for title, and 'F. Scott Fitzgerald' for author.

MySQL

CREATE TABLE books (
  id INT PRIMARY KEY,
  title VARCHAR(100),
  author VARCHAR(100)
);
-- Your code here to insert a new book

Hint

Use INSERT INTO books (id, title, author) VALUES (1, 'The Great Gatsby', 'F. Scott Fitzgerald');

3

Verify the insertion

Write a SQL statement to select all columns from the books table to verify the new row was inserted.

MySQL

CREATE TABLE books (
  id INT PRIMARY KEY,
  title VARCHAR(100),
  author VARCHAR(100)
);

INSERT INTO books (id, title, author) VALUES (1, 'The Great Gatsby', 'F. Scott Fitzgerald');
-- Your code here to select all rows

Hint

Use SELECT * FROM books; to see all rows in the table.

4

Add a final comment

Add a SQL comment at the end of your code that says -- Insert complete to mark the completion of your insert operation.

MySQL

CREATE TABLE books (
  id INT PRIMARY KEY,
  title VARCHAR(100),
  author VARCHAR(100)
);

INSERT INTO books (id, title, author) VALUES (1, 'The Great Gatsby', 'F. Scott Fitzgerald');

SELECT * FROM books;
-- Your comment here

Hint

Add -- Insert complete at the end of your SQL code.

Practice

1. What does the INSERT INTO statement do in MySQL?

easy

A. Creates a new table

B. Deletes a row from a table

C. Adds a new row to a table

D. Updates existing rows in a table

Solution

1. Step 1: Understand the purpose of INSERT INTO

   The INSERT INTO statement is used to add new data rows into an existing table.

2. Step 2: Compare with other SQL commands

   Deleting removes rows, updating changes existing rows, and creating makes new tables, so these are different commands.

3. Final Answer:

   Adds a new row to a table -> Option C

4. Quick Check:

   INSERT INTO = Add row [OK]

Hint: INSERT INTO always adds new rows, not deletes or updates [OK]

Common Mistakes:

• Confusing INSERT with DELETE or UPDATE
• Thinking INSERT creates tables
• Assuming INSERT modifies existing rows

2. Which of the following is the correct syntax to insert a single row into a table named users with columns id and name?

easy

A. INSERT users INTO (id, name) VALUES (1, 'Alice');

B. INSERT INTO users (id, name) VALUES (1, 'Alice');

C. INSERT INTO users VALUES id=1, name='Alice';

D. INSERT INTO users (id, name) SET (1, 'Alice');

Solution

1. Step 1: Check the standard INSERT INTO syntax

   The correct syntax is INSERT INTO table_name (columns) VALUES (values); which matches INSERT INTO users (id, name) VALUES (1, 'Alice');.

2. Step 2: Identify errors in other options

   INSERT users INTO (id, name) VALUES (1, 'Alice'); has wrong order of keywords, C uses invalid assignment syntax, and D uses SET incorrectly.

3. Final Answer:

   INSERT INTO users (id, name) VALUES (1, 'Alice'); -> Option B

4. Quick Check:

   INSERT INTO ... VALUES (...) is correct syntax [OK]

Hint: Remember: INSERT INTO table (cols) VALUES (vals); [OK]

Common Mistakes:

• Swapping keywords order
• Using SET instead of VALUES
• Incorrect assignment inside VALUES

3. Given the table products(id INT, name VARCHAR(20), price DECIMAL(5,2)), what will be the result of this query?
INSERT INTO products (id, name, price) VALUES (10, 'Pen', 1.50); SELECT * FROM products WHERE id = 10;

medium

A. [{"id":10, "name":"Pen", "price":1.50}]

B. Syntax error due to missing semicolon

C. Empty result, no rows inserted

D. [{"id":null, "name":"Pen", "price":1.50}]

Solution

1. Step 1: Analyze the INSERT statement

   The query inserts a row with id=10, name='Pen', price=1.50 into the products table.

2. Step 2: Check the SELECT query result

   The SELECT fetches the row with id=10, which was just inserted, so it returns that row.

3. Final Answer:

   [{"id":10, "name":"Pen", "price":1.50}] -> Option A

4. Quick Check:

   Inserted row is returned by SELECT [OK]

Hint: Inserted row appears in SELECT immediately after insert [OK]

Common Mistakes:

• Assuming insert fails without error
• Expecting empty result after insert
• Confusing syntax errors with correct queries

4. Identify the error in this query:
INSERT INTO employees (id, name, salary) VALUES (5, John, 3000);

medium

A. Salary should be a string

B. Missing parentheses around VALUES

C. Wrong table name

D. Missing quotes around the string 'John'

Solution

1. Step 1: Check string value syntax

   String values like names must be enclosed in single quotes in SQL, but 'John' is unquoted here.

2. Step 2: Verify other parts of the query

   Parentheses around VALUES are correct, table name is plausible, and salary is numeric so no quotes needed.

3. Final Answer:

   Missing quotes around the string 'John' -> Option D

4. Quick Check:

   Strings need quotes in VALUES [OK]

Hint: Always quote text values in INSERT [OK]

Common Mistakes:

• Forgetting quotes for text
• Confusing numeric and string types
• Misplacing parentheses

5. You have a table orders(order_id INT, customer VARCHAR(50), total DECIMAL(7,2)). You want to insert a new order with order_id 101, customer name "O'Reilly", and total 250.75. Which query correctly inserts this row?

hard

A. INSERT INTO orders (order_id, customer, total) VALUES (101, 'O''Reilly', 250.75);

B. INSERT INTO orders (order_id, customer, total) VALUES (101, 'O\'Reilly', 250.75);

C. INSERT INTO orders (order_id, customer, total) VALUES (101, 'O'Reilly', 250.75);

D. INSERT INTO orders (order_id, customer, total) VALUES (101, "O'Reilly", 250.75);

Solution

1. Step 1: Understand how to escape single quotes in SQL strings

   In SQL, single quotes inside strings are escaped by doubling them: 'O''Reilly'.

2. Step 2: Evaluate each option's string quoting

   INSERT INTO orders (order_id, customer, total) VALUES (101, 'O'Reilly', 250.75); breaks string due to unescaped single quote. INSERT INTO orders (order_id, customer, total) VALUES (101, 'O\'Reilly', 250.75); uses backslash which is not standard in MySQL. INSERT INTO orders (order_id, customer, total) VALUES (101, "O'Reilly", 250.75); uses double quotes which are not string delimiters in SQL. INSERT INTO orders (order_id, customer, total) VALUES (101, 'O''Reilly', 250.75); correctly doubles the single quote.

3. Final Answer:

   INSERT INTO orders (order_id, customer, total) VALUES (101, 'O''Reilly', 250.75); -> Option A

4. Quick Check:

   Escape single quote by doubling it [OK]

Hint: Escape single quote inside strings by doubling it '' [OK]

Common Mistakes:

• Using unescaped single quotes inside strings
• Using backslash escape in MySQL strings
• Using double quotes for string literals