Recent questions tagged goclasses-cs-dpp-day-362

Let $K_1$ and $K_2$ be two distinct candidate keys of a relation $R$.Let $S_1$ and $S_2$ be two superkeys of $R$.Which of the following statements are always true?$K_1\cu...

Consider the relation schema $R(A,B,C,D,E)$.It is known that $R$ has exactly two candidate keys, and one of them is ${A,B}$.What are the maximum and minimum possible numb...

A relation schema $R$ has $6$ attributes.What is the maximum number of candidate keys that $R$ can simultaneously have?

A relation schema $R$ has $6$ attributes.Assume that the empty set is not considered a key.What is the maximum possible number of superkeys of $R$?

Consider the following relation instance $R(A,B,C)$:$$\begin{array}{|c|c|c|}\hlineA & B & C \\\hline\alpha & \delta & \xi \\\beta & \delta & \psi \\\gamma & \eta & \xi \\...

Consider the following grammar$$\begin{aligned}S &\to AA \\A &\to AAA \mid bA \mid Ab \mid a\end{aligned}$$Which of the following strings can be used as a witness to show...

Which CFG generates the set of all properly balanced strings of parentheses, including $\epsilon$, the parentheses must be properly nested. Some sample strings in the lan...

Let's imagine that you're going for a walk with your dog, but this time don't have a leash. Let $\Sigma = \{y,d\}$, where $y$ means that you take a step forward and $d$ m...

Let $\Sigma = \{1,+,=\}$ then which of the following CFG generates the language $L = \{1^m+1^n=1^{m+n} \mid m,n \in \mathbb{N}\}$. For example, the strings $111+1=1111$ a...

Let $\Sigma = \{a,b\}$ and $L = \{w \in \Sigma^* \mid w$ is not a palindrome$\}$, i.e, the language of strings that are not the same when read forwards and backwards. For...