Question

Structure of the CUSTOMERS table

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Structure of the ORDERS table



Structure of the ORDERITEMS table



Structure of the BOOKS table




​ To display the name of each customer and the ISBN of each book purchased by the customers would require how many joins in the FROM clause of the SQL statement?

Answer 1

Three joins are required in the FROM clause of the SQL statement to display the name of each customer and the ISBN of each book purchased; these joins connect the CUSTOMERS, ORDERS, ORDERITEMS, and BOOKS tables.

Step-by-step explanation:

To display the name of each customer and the ISBN of each book purchased by the customers, we need to consider the relationships between the CUSTOMERS, ORDERS, ORDERITEMS, and BOOKS tables. Assuming the CUSTOMERS table has a primary key that relates to a foreign key in the ORDERS table, the ORDERS table has a primary key that relates to a foreign key in the ORDERITEMS table, and the ORDERITEMS table has a foreign key that relates to the primary key in the BOOKS table, we would need the following joins in the SQL FROM clause:

1. A join between the CUSTOMERS table and the ORDERS table to link customers to their orders.
2. A join between the ORDERS table and the ORDERITEMS table to link orders to their items.
3. A join between the ORDERITEMS table and the BOOKS table to get the ISBNs of the books ordered.

Therefore, we would require three joins in the FROM clause of the SQL statement to achieve this result.