LAB EXAM - Database Systems
Duration: 60 minutes
Import database classicmodels by executing ​mysqlsampledatabase.sql ​script that you can
find on LMS.
The database that we will use for this lab exam is called classicmodels. ​The ​classicmodels
database is a retailer of scale models of classic cars database. It contains typical business data
such as customers, products, sales orders, sales order line items, etc. This database schema
consists of the following tables:
-
Customers​: stores customer’s data.
Products​: stores a list of scale model cars.
Orders​: stores sales orders placed by customers.
OrderDetails​: stores sales order line items for each sales order.
Payments​: stores payments made by customers based on their accounts.
Employees​: stores all employee information as well as the organization structure such
as who reports to whom.
- Offices​: stores sales office data.
------------------------------------------------------------------------------------------------------------------------------1. (25%) Write SQL query that will, for every customer and every product, return a total quantity
of ordered products (total_quantity) together with the customer name and product name. Order
result set by total_quantity in descending order.
The query will return 2532 rows.
Hint:​ Add ​LIMIT 3000 ​to your query in order to verify that the correct number of rows is returned.
Tables needed​: customers, orders, orderdetails, products
------------------------------------------------------------------------------------------------------------------------------2. (35%) ​Write a SQL query that will return the total amount of payments for every employee in
every country and every city where the payment date is greater than 2004-12-15. The query
should also return a comma-separated list of payment check numbers (use GROUP_CONCAT
function). Order result set in descending order by country column.
The query will return 14 rows.
Tables needed:​ offices, employees, customers, payments
------------------------------------------------------------------------------------------------------------------------------3. (40%) ​Write MySQL function (name of the function should be ​customer_level​) that will
receive customer number as a parameter. The function will get the total amount of payments for
that customer and check in which category customer belongs to and return the output as
follows:
Conditions
Output
customer_sales > 50000 AND customer_sales <= 100000
'GOOD'
customer_sales > 100000 AND customer_sales <= 150000
'BETTER'
customer_sales > 150000
‘BEST’
None of the conditions are satisfied
‘WORST’
Tables needed: ​customers, payments
In order to check if the function is working properly invoke the following commands and output
should be as written next to the select statement
SELECT customer_level(114) - o
​ utput should be ​‘BEST’
SELECT customer_level(103) - o
​ utput should be ​‘WORST’
Hint: F
​ unction skeleton
DELIMITER $$
CREATE​ ​FUNCTION​ function_name(
param1,
param2,…
)
RETURNS​ datatype
[​NOT​] ​DETERMINISTIC
BEGIN
​-- statements
END​ $$
DELIMITER ;