Suppose the adjacency relation of vertices in a graph is represented in a table Adj (X, Y). Which of the following queries cannot be expressed by a relational algebra expression of constant length?

List of all vertices adjacent to a given vertex

List of all vertices which have self loops

List of all vertices which belong to cycles of less than three vertices

List of all vertices reachable from a given vertex

Suppose the adjacency relation of vertices in a graph is represented i

1.	Suppose the adjacency relation of vertices in a graph is represented in a table Adj (X, Y). Which of the following queries cannot be expressed by a relational algebra expression of constant length?
A.	List of all vertices adjacent to a given vertex
B.	List of all vertices which have self loops
C.	List of all vertices which belong to cycles of less than three vertices
D.	List of all vertices reachable from a given vertex
Answer» E.

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Suppose the adjacency relation of vertices in a graph is represented in a table Adj (X, Y). Which of the following queries cannot be expressed by a relational algebra expression of constant length?

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