SQL

Q41.

Which of the following statements are TRUE about an SQL query? P : An SQL query can contain a HAVING clause even if it does not have a GROUP BY clause Q : An SQL query can contain a HAVING clause only if it has a GROUP BY clause R : All attributes used in the GROUP BY clause must appear in the SELECT clause S : Not all attributes used in the GROUP BY clause need to appear in the SELECT clause
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Q42.

Consider a database table T containing two columns X and Y each of type integer. After the creation of the table, one record (X=1,Y=1) is inserted in the table. Let MX and MY denote the respective maximum values of X and Y among all records in the table at any point in time. Using MX and MY, new records are inserted in the table 128 times with X and Y values being MX+1, 2*MY+1 respectively. It may be noted that each time after the insertion, values of MX and MY change. What will be the output of the following SQL query after the steps mentioned above are carried out? SELECT Y FROM T WHERE X=7;
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Q43.

Consider the table employee(empId, name, department, salary) and the two queries Q1 ,Q2 below. Assuming that department 5 has more than one employee, and we want to find the employees who get higher salary than anyone in the department 5, which one of the statements is TRUE for any arbitrary employee table?Q1 : Select e.empId From employee e Where not exists (Select * From employee s where s.department = "5" and s.salary >=e.salary) Q2 : Select e.empId From employee e Where e.salary > Any (Select distinct salary From employee s Where s.department ="5"
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Q44.

Consider the following relational schema:Student(school-id,sch-roll-no,sname,saddress) School(school-id,sch-name,sch-address,sch-phone) Enrolment(school-id,sch-roll-no,erollno,examname) ExamResult(erollno,examname,marks) What does the following SQL query output?SELECT sch-name, COUNT (*) FROM School C, Enrolment E, ExamResult R WHERE E.school-id = C.school-id AND E.examname = R.examname AND E.erollno = R.erollno AND R.marks = 100 AND S.school-id IN (SELECT school-id FROM student GROUP BY school-id HAVING COUNT (*) > 200) GROUP By school-id
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Q45.

Consider the following schema:Emp (Empcode, Name, Sex, Salary, Deptt)A simple SQL query is executed as follows: SELECT Deptt FROM Emp GROUP by Dept Having avg (Salary) > {select avg (Salary) from Emp}The output will be
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