List of top Database Management Systems Questions on Normal Forms

In a relational data model, which one of the following statements is TRUE?

Suppose the following functional dependencies hold on a relation \(U\) with attributes \(P, Q, R, S,\) and \(T\):
\[ P \rightarrow QR, RS \rightarrow T \] Which of the following functional dependencies can be inferred from the above functional dependencies?

Consider the relation \(R(P,Q,S,T,X,Y,Z,W)\) with the following functional dependencies:
\[ PQ \rightarrow X; P \rightarrow YX; Q \rightarrow Y; Y \rightarrow ZW \] Consider the decomposition of the relation \(R\) into the constituent relations according to the following two decomposition schemes. \[ \begin{aligned} D_1 &: R = [(P,Q,S,T);\; (P,T,X);\; (Q,Y);\; (Y,Z,W)] \\ D_2 &: R = [(P,Q,S);\; (T,X);\; (Q,Y);\; (Y,Z,W)] \end{aligned} \] Which one of the following options is correct?