w3resource
SQL exercises

SQL Subquery Exercises: Find the salesmen who have multiple customers

SQL SUBQUERY: Exercise-16 with Solution

16. Write a query to find the salesmen who have multiple customers.

Sample table: Customer


Sample table: Salesman


Sample Solution:

SELECT * 
FROM salesman 
WHERE salesman_id IN (
   SELECT DISTINCT salesman_id 
   FROM customer a 
   WHERE EXISTS (
      SELECT * 
      FROM customer b 
      WHERE b.salesman_id=a.salesman_id 
      AND b.cust_name<>a.cust_name));

Sample Output:

salesman_id	name		city	commission
5001		James Hoog	New York	0.15
5002		Nail Knite	Paris		0.13

Explanation:

SQL Subqueries:  Find the salesmen who have multiple customers.

Practice Online


Inventory database model

Query Visualization:

Duration:

Query visualization of Find the salesmen who have multiple customers - Duration

Rows:

Query visualization of Find the salesmen who have multiple customers - Rows

Cost:

Query visualization of Find the salesmen who have multiple customers - Cost

Contribute your code and comments through Disqus.

Previous: Write a query to extract the data from the customer table if and only if one or more of the customers in the customer table are located in London.
Next: Write a query to find all the salesmen who worked for only one customer.

What is the difficulty level of this exercise?



New Content: Composer: Dependency manager for PHP, R Programming