Preparation for Tutorial:

CREATE TABLE users2 (
user_id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
first_name VARCHAR(55) NOT NULL,
num_of_pets TINYINT,
has_pets BIT);

INSERT INTO users2
(USER_ID, first_name, num_of_pets, has_pets)
VALUES
(NULL, "Bob", 6, NULL),
(NULL, "bobby", 3, NULL),
(NULL, "Susie", 1, NULL),
(NULL, "Cindy", 4, NULL),
(NULL, "Brian", 3, NULL),
(NULL, "REbecca", 3, NULL),
(NULL, "Daniel", 1, NULL),
(NULL, "Tim", 3, NULL),
(NULL, "Danielle", 1, NULL),
(NULL, "richard", 1, 1);