Consider the following two tables and four queries in SQL.Book (isbn, bname), Stock (isbn, copies)Query 1: SELECT B.isbn, S.copiesFROM Book B INNER JOIN Stock SON B.isbn = S.isbn; Query 2: SELECT B.isbn, S.copiesFROM Book B LEFT OUTER JOIN Stock SON B.isbn = S.isbn;Query 3: SELECT B.isbn, S.copiesFROM Book B RIGHT OUTER JOIN Stock SON B.isbn = S.isbn; Query 4: SELECT B.isbn, S.copiesFROM Book B FULL OUTER JOIN Stock SON B.isbn = S.isbn; Which one of the queries above is certain to have an output that is a superset of the outputsof the other three queries?

Consider the following two tables and four queries in SQL.Book (isbn,

1.	Consider the following two tables and four queries in SQL.Book (isbn, bname), Stock (isbn, copies)Query 1: SELECT B.isbn, S.copiesFROM Book B INNER JOIN Stock SON B.isbn = S.isbn; Query 2: SELECT B.isbn, S.copiesFROM Book B LEFT OUTER JOIN Stock SON B.isbn = S.isbn;Query 3: SELECT B.isbn, S.copiesFROM Book B RIGHT OUTER JOIN Stock SON B.isbn = S.isbn; Query 4: SELECT B.isbn, S.copiesFROM Book B FULL OUTER JOIN Stock SON B.isbn = S.isbn; Which one of the queries above is certain to have an output that is a superset of the outputsof the other three queries?
A.	Query 1
B.	Query 2
C.	Query 3
D.	Query 4
Answer» E.

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