Suppose We Wish To Find The Ids Of The Employees That Are #548

Suppose we wish to find the ID’s of the employees that are managed by people who are managed by the employee with ID 123. Here are two possible queries:</p> <pre><code class="language-sql">I.SELECT ee.empID FROM Emps ee, Emps ff WHERE ee.mgrID = ff.empID AND ff.mgrID = 123; II.SELECT empID FROM Emps WHERE mgrID IN (SELECT empID FROM Emps WHERE mgrID = 123);</code></pre> <p>Which, if any, of the two queries above will correctly (in SQL2) get the desired set of employee ID’s?

This multiple choice question (MCQ) is related to the book/course gs gs117 Database Management System. It can also be found in gs gs117 Normalization in Database Management System - Functional-Dependency Theory - Quiz No.1.

I.SELECT ee.empID FROM Emps ee, Emps ff WHERE ee.mgrID = ff.empID AND ff.mgrID = 123; II.SELECT empID FROM Emps WHERE mgrID IN (SELECT empID FROM Emps WHERE mgrID = 123);