QUESTION 8 Given table R(A,B,C) and S(C,D,E), which of the following SQL stateme

Question

QUESTION 8

Given table R(A,B,C) and S(C,D,E), which of the following SQL statements would find the record(s) with null values on the column C in table R?

a.   select * from R left outer join S where R.C = S.C;

b.     select * from R right outer join S where R.C = S.C;

c.   either a. or b.

d.   neither a. nor b.

QUESTION 11

If there is a one-to-many relationship between entity A and B, then

a.   there exists a functional dependency from the primary key in A to the primary key in B, i.e.,
PK(A) ? PK(B).

b.   there exists a functional dependency from the primary key in B to the primary key in A, i.e.,
PK(B) ? PK(A).

c.   both a. and b.

d.   neither a. nor b.

QUESTION 12

In __________________, the number of (first-level) index entries is equal to the number of distinct index values in data file.

a.   primary index

b.   cluster index

c.   secondary index

d.   multi-level index

Explanation / Answer

8.(b) is the answer.

Because in right outer join it gives all the rows from the right side and the matching rows from lift side if there is no matching in left then null values it gives.

11. (d) neither a nor b

Because to show one to many relationship the table A must have one primary key and the table B must have the foreign key column referring the table A primary key column, then only one to many relationship will exists.

12. (c) secondary index

In secondary index no of index entries is equal to no of distinct index values.

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