SQL Exercises: Orders of the salesman working for the customer 3007

SQL SUBQUERY : Exercise-3 with Solution

3. From the following tables write a SQL query to find all orders generated by the salespeople who may work for customers whose id is 3007. Return ord_no, purch_amt, ord_date, customer_id, salesman_id.

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 Solution:

-- Selecting all columns from the 'orders' table
SELECT *
-- Specifying the table to retrieve data from ('orders')
FROM orders
-- Filtering the results based on the condition that 'salesman_id' is equal to the result of a subquery
WHERE salesman_id =
    -- Subquery: Selecting distinct 'salesman_id' from the 'orders' table where 'customer_id' is 3007
    (SELECT DISTINCT salesman_id 
     FROM orders 
     WHERE customer_id = 3007);

Output of the Query:

ord_no	purch_amt	ord_date	customer_id	salesman_id
70002	65.26		2012-10-05	3002		5001
70005	2400.60		2012-07-27	3007		5001
70008	5760.00		2012-09-10	3002		5001
70013	3045.60		2012-04-25	3002		5001

Explanation:

The said SQL query selects all columns (*) from the orders table where the 'salesman_id' is equal to the distinct 'salesman_id' from the orders table where the 'customer_id' is equal to 3007. In other words, it is selecting all rows from the orders table where the salesman who serviced a customer with the ID of 3007, also serviced.

Visual Explanation:

Practice Online

Sample Database: inventory

Query Visualization:

Duration:

Rows:

Cost:

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