Consider the relational database with the following four schemas and their respective instances.

Student( $$\underline {sNo} $$ , sName, dNo) Dept( $$\underline {dNo} $$ , dName)

Course( $$\underline {cNo} $$ , cName, dNo) Register( $$\underline {sNo} $$ , $$\underline {cNo} $$ )

SQL Query :

SELECT * FORM Student AS S WHERE NOT EXIST

(SELECT cNo FROM Course WHERE dNo = "D01"

EXCEPT

SELECT cNo FROM Register WHERE sNo = S.sNo)

The number of rows returned by the above SQL query is _____________.

Consider a relational database containing the following schemas.
The primary key of each table is indicated by underlying the constituent fields.

SELECT s.sno, s.sname

FROM Suppliers s, Catalogue c

WHERE s.sno = c.sno AND

      Cost > (SELECT AVG (cost)

                 FROM Catalogue

                 WHERE pno = ‘P4’

                 GROUP BY pno);

The number of rows returned by the above SQL query is

Consider the following two tables and four queries in SQL.

Book (isbn, bname), Stock (isbn, copies)

Query 1:

SELECT B.isbn, S.copies
 FROM Book B INNER JOIN Stock S
 ON B.isbn = S.isbn;

Query 2:

SELECT B.isbn, S.copies
 FROM Book B LEFT OUTER JOIN Stock S
 ON B.isbn = S.isbn;

Query 3:

SELECT B.isbn, S.copies
 FROM Book B RIGHT OUTER JOIN Stock S
 ON B.isbn = S.isbn;

Query 4:

SELECT B.isbn, S.copies
 FROM Book B FULL OUTER JOIN Stock S
 ON B.isbn = S.isbn;

Which one of the queries above is certain to have an output that is a superset of the outputs of the other three queries?

SELECT operation in SQL is equivalent to