SQL Exercise: Display commission of the salesman for an order

SQL JOINS: Exercise-6 with Solution

From the following tables write a SQL query to find the details of an order. Return ord_no, ord_date, purch_amt, Customer Name, grade, Salesman, commission.

Sample table: orders

ord_no      purch_amt   ord_date    customer_id  salesman_id
----------  ----------  ----------  -----------  -----------
70001       150.5       2012-10-05  3005         5002
70009       270.65      2012-09-10  3001         5005
70002       65.26       2012-10-05  3002         5001
70004       110.5       2012-08-17  3009         5003
70007       948.5       2012-09-10  3005         5002
70005       2400.6      2012-07-27  3007         5001
70008       5760        2012-09-10  3002         5001
70010       1983.43     2012-10-10  3004         5006
70003       2480.4      2012-10-10  3009         5003
70012       250.45      2012-06-27  3008         5002
70011       75.29       2012-08-17  3003         5007
70013       3045.6      2012-04-25  3002         5001

Sample table: customer

 customer_id |   cust_name    |    city    | grade | salesman_id 
-------------+----------------+------------+-------+-------------
        3002 | Nick Rimando   | New York   |   100 |        5001
        3007 | Brad Davis     | New York   |   200 |        5001
        3005 | Graham Zusi    | California |   200 |        5002
        3008 | Julian Green   | London     |   300 |        5002
        3004 | Fabian Johnson | Paris      |   300 |        5006
        3009 | Geoff Cameron  | Berlin     |   100 |        5003
        3003 | Jozy Altidor   | Moscow     |   200 |        5007
        3001 | Brad Guzan     | London     |       |        5005

Sample table: salesman

 salesman_id |    name    |   city   | commission 
-------------+------------+----------+------------
        5001 | James Hoog | New York |       0.15
        5002 | Nail Knite | Paris    |       0.13
        5005 | Pit Alex   | London   |       0.11
        5006 | Mc Lyon    | Paris    |       0.14
        5007 | Paul Adam  | Rome     |       0.13
        5003 | Lauson Hen | San Jose |       0.12

Sample Solution:

-- Selecting specific columns and renaming them for clarity
SELECT a.ord_no, a.ord_date, a.purch_amt,
       b.cust_name AS "Customer Name", b.grade, 
       c.name AS "Salesman", c.commission 
-- Specifying the table to retrieve data from ('orders' as 'a')
FROM orders a 
-- Performing an inner join with 'customer' table ('b') based on customer_id
INNER JOIN customer b 
ON a.customer_id = b.customer_id 
-- Performing another inner join with 'salesman' table ('c') based on salesman_id
INNER JOIN salesman c 
ON a.salesman_id = c.salesman_id;

Output of the Query:

 ord_no	ord_date	purch_amt	Customer Name	grade	Salesman	commission
70009	2012-09-10	270.65		Brad Guzan		Pit Alex	0.11
70002	2012-10-05	65.26		Nick Rimando	100	James Hoog	0.15
70004	2012-08-17	110.50		Geoff Cameron	100	Lauson Hen	0.12
70005	2012-07-27	2400.60		Brad Davis	200	James Hoog	0.15
70008	2012-09-10	5760.00		Nick Rimando	100	James Hoog	0.15
70010	2012-10-10	1983.43		Fabian Johnson	300	Mc Lyon		0.14
70003	2012-10-10	2480.40		Geoff Cameron	100	Lauson Hen	0.12
70011	2012-08-17	75.29		Jozy Altidor	200	Paul Adam	0.13
70013	2012-04-25	3045.60		Nick Rimando	100	James Hoog	0.15
70001	2012-10-05	150.50		Graham Zusi	200	Nail Knite	0.13
70007	2012-09-10	948.50		Graham Zusi	200	Nail Knite	0.13
70012	2012-06-27	250.45		Julian Green	300	Nail Knite	0.13

Explanation:

The said SQL query that uses the INNER JOIN clause to combine rows from three tables: orders, customer, and salesman.
The query retrieves the ord_no, ord_date, purch_amt, cust_name, grade, name, and commission from the three tables where the customer_id from the orders table matches the customer_id from the customer table, and the salesman_id from the orders table matches the salesman_id from the salesman table.
The query also uses the AS keyword to rename the cust_name and name columns as 'Customer Name' and 'Salesman' respectively.

Visual Explanation:

Practice Online

Query Visualization:

Duration:

Rows:

Cost:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous SQL Exercise: Customers and salespeople live in different cities.
Next SQL Exercise: Join within the tables salesman, customer and orders.