SQL Subquery Exercises: Find all the salesmen worked for only one customer
SQL SUBQUERY: Exercise-17 with Solution
17. Write a query to find all the salesmen who worked for only one customer.
Sample table: Customer
Sample table: Salesman
SELECT * FROM salesman WHERE salesman_id IN ( SELECT DISTINCT salesman_id FROM customer a WHERE NOT EXISTS ( SELECT * FROM customer b WHERE a.salesman_id=b.salesman_id AND a.cust_name<>b.cust_name));
salesman_id name city commission 5005 Pit Alex London 0.11 5006 Mc Lyon Paris 0.14 5007 Paul Adam Rome 0.13 5003 Lauson Hen San Jose0.12
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