1
GATE CSE 1997
+2
-0.6
For a database relation $$R(a,b,c,d),$$ where the domains of $$a, b, c, d$$ include only atomic values, only the following functional dependencies and those that can be inferred from them hold:
$$a \to c\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,b \to d$$
This relation is
A
In $$1$$ $$NF$$ but not in $$2$$ $$NF$$
B
In $$2$$ $$NF$$ but not in $$3$$ $$NF$$
C
In $$3$$ $$NF$$
D
None of the above
2
GATE CSE 1997
+2
-0.6
Let $$R (a, b, c)$$ and $$S(d, e, f)$$ be two relations in which $$d$$ is the foreign key of $$S$$ that refers to the primary key of $$R.$$ Consider the following four operations $$R$$ and $$S$$
(a) Insert into $$R$$ (b) Insert into $$S$$
(c) Delete from $$R$$ (d) Delete from $$S Which of the following statements is true about the referential integrity constraint above? A None of (a), (b), (c) or (d) can cause its violation B All of (a), (b), (c) and (d) can cause its violation C Both (a) and (d) can cause its violation D Both (b) and (c) can cause its violation 3 GATE CSE 1995 Subjective +2 -0 (a) Consider the relation scheme$$R(A, B, C)$$with the following functional dependencies:$$\eqalign{ & A,B \to C \cr & \,\,\,\,\,\,C \to A \cr} $$Show that the scheme$$R$$is the Third Normal Form$$(3NF)$$but not in Boyce-Code Normal Form$$(BCNF).$$(b) Determine the minimal keys of relation$$R.

GATE CSE Subjects
EXAM MAP
Medical
NEET