MySQL 5.7

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CREATE TABLE Purchasing (
    purchasing_id int auto_increment primary key,
    campaign VARCHAR(255),
    main_event VARCHAR(255),
    sub_event VARCHAR(255),
    quantity VARCHAR(255)
);

INSERT INTO Purchasing
(campaign, main_event, sub_event, quantity)
VALUES 
("C001", "Offered", NULL, "500"),
("C001", "Ordered", NULL, "450"),
("C001", "Storing", "Delivered", "465"),
("C001", "Storing", "Recorded", "440"),
("C001", "Storing", "Completed", "445"),

("C002", "Offered", NULL, "600"),
("C002", "Ordered", NULL, "700"),
("C002", "Storing", "Delivered", "690"),
("C002", "Storing", "Recorded", "692"),

("C003", "Offered", NULL, "300"),
("C003", "Ordered", NULL, "250"),
("C003", "Storing", "Delivered", "320"),

("C004", "Offered", NULL, "800"),
("C004", "Ordered", NULL, "870"),
("C004", "Storing", "Delivered", "740"),

("C005", "Offered", NULL, "240"),
("C005", "Ordered", NULL, "250"),
("C005", "Storing", "Delivered", "226"),

("C006", "Offered", NULL, "100"),
("C006", "Ordered", NULL, "105"),

("C007", "Offered", NULl, "900"),
("C008", "Offered", NULl, "400");

Records: 22  Duplicates: 0  Warnings: 0

purchasing_id	campaign	main_event	sub_event	quantity
5	C001	Storing	Completed	445
9	C002	Storing	Recorded	692
12	C003	Storing	Delivered	320
15	C004	Storing	Delivered	740
18	C005	Storing	Delivered	226
20	C006	Ordered	null	105
21	C007	Offered	null	900
22	C008	Offered	null	400