candidate-key

Consider the following relational schema along with all the functional dependencies that hold on them. $$\begin{aligned} & R 1(A, B, C, D, E):\{D \rightarrow E, E A \rightarrow B,...

Which of the following statements about a relation $R$ in first normal form (1NF) is/are TRUE?

The maximum number of superkeys for the relation schema $$R(E, F, G, H)$$ with $$E$$ as key is ______.

Consider the relation schema $$R = \left( {E,\,F,\,G,\,H,\,I,\,J,\,K,L,\,M,\,N} \right)$$ and the set of functional dependencies $$\left\{ {\left\{ {E,F} \right\} \to \left\{ G \ri...

A prime attribute of a relation scheme $$R$$ is an attribute that appears

Relation $$R$$ has eight attribution $$ABCDEFGH.$$ Fields of $$R$$ contain only atomic values. $$F = \left\{ {CH \to G,\,\,A \to BC,\,B \to CFH,\,\,E \to A,\,\,F \to EG} \right\}$$...

Consider a relation table with a single record for each registered student with a single record for each registered student with the following attributes. $$1.$$ $$Registration$$ $...

The following functional dependencies hold for relations R(A, B, C) and S(B, D, E): $$$\eqalign{ & B \to A \cr & A \to C \cr} $$$ The relation R contains 200 tuples and the relatio...

Let $$R\left( {A,\,B,\,C,\,D,E,P,G} \right)$$ be a relational schema in which the following functional dependencies are known to hold: $$AB \to CD,\,\,DE \to P,\,\,C \to E.\,\,P \t...

A table has fields, $$F1, F2, F3, F4, F5,$$ with the following functional dependencies: $$F1 \to F3.\,F2 \to F4.\,\,\,\left( {F1\,.\,F2} \right) \to F5$$ in terms of Normalization,...

Consider a relation scheme $$R = \left( {A,\,B,\,C,\,D,\,E,\,H} \right)$$ on which the following functional dependencies hold: $$\left\{ {A \to B,\,\,BC \to D,\,\,E \to C,\,\,D \to...

Consider the following functional dependencies in a database. $$\eqalign{ & \,\,\,\,Date\,\,of\,\,Birth\,\, \to \,\,Age \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,Ag...

Let $$R=(A,B,C,D,E,F)$$ be a relation scheme with the following dependencies: $$C \to F,\,E \to A,\,EC \to D,\,A \to B.$$ Which of the following is a key for $$R?$$

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 fr...

(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...

An instance of a relational scheme R(A, B, C) has distinct values for attribute A. Can you conclude that A is a candidate key for R?