Consider the following relational schema:employee(empId,empName,empDept)customer(custId,custName,salesRepId,rating)salesRepId is a foreign key referring to empId of the employee relation. Assume that eachemployee makes a sale to at least one customer. What does the following query return?SELECT empName FROM employee EWHERE NOT EXISTS (SELECT custId FROM customer C WHERE C.salesRepId = E.empIdAND C.rating ’GOOD’);

Names of all the employees with at least one of their customers having a ‘GOOD’ rating.

Names of all the employees with at most one of their customers having a ‘GOOD’ rating.

Names of all the employees with none of their customers having a ‘GOOD’ rating.

Names of all the employees with all their customers having a ‘GOOD’ rating.

Consider the following relational schema:employee(empId,empName,empDep

1.	Consider the following relational schema:employee(empId,empName,empDept)customer(custId,custName,salesRepId,rating)salesRepId is a foreign key referring to empId of the employee relation. Assume that eachemployee makes a sale to at least one customer. What does the following query return?SELECT empName FROM employee EWHERE NOT EXISTS (SELECT custId FROM customer C WHERE C.salesRepId = E.empIdAND C.rating <> ’GOOD’);
A.	Names of all the employees with at least one of their customers having a ‘GOOD’ rating.
B.	Names of all the employees with at most one of their customers having a ‘GOOD’ rating.
C.	Names of all the employees with none of their customers having a ‘GOOD’ rating.
D.	Names of all the employees with all their customers having a ‘GOOD’ rating.
Answer» E.

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