The subquery is:
select f.sex from professor f where f.empid = s.advisor
Here, the subquery uses s.advisor from the outer query.
So, it is a correlated subquery.
Therefore, S1 is true and S2 is false.
Also, advisor refers to empid of professor relation. Since empid is unique, the subquery returns only one professor’s sex.
So,
s.sex = ALL (single value)
and
s.sex = ANY (single value)
will give the same result.
Therefore, S4 is true and S3 is false.
Online Test Series, Information About Examination,
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Online Test Series, Information About Examination,
Syllabus, Notification
and More.