--%>

Problem on Datalog for defining properties

The focus is on  the use of Datalog for defining properties  and queries on graphs.

(a) Assume that P is some property of graphs  definable in the Datalog. Show that P is preserved beneath extensions  and homomorphisms. That is, when G is a graph satisfying P, then for every supergraph of G (i.e., graph  extending G) satisfies  P, and  when h is a graph homomorphism, then h(G) satisfies P. Which of the below properties  and queries on graphs are definable in the Datalog?

(b) The number  of vertices  are even.

(c) There is a simple path (that is, a path without repeated vertices) of even length among two specified vertices.

(d) The binary relation? Having all pairs of vertices (a, b) for which  there  is a path of even length from a to b.

Given either a Datalog program stating the property or query or an argument why the property or query is not definable in the Datalog.

   Related Questions in Mathematics

  • Q : Who firstly discovered mathematical

    Who firstly discovered mathematical theory for random walks, that rediscovered later by Einstein?

  • Q : Problem on sales and budget XYZ Farm

    XYZ Farm Supply data regarding the store's operations follow: • Sales are budgeted at $480,000 for November, $430,000 for December, and $340,000 for January. • Collections are expected

  • Q : Pig Game Using the PairOfDice class

    Using the PairOfDice class design and implement a class to play a game called Pig. In this game the user competes against the computer. On each turn the player rolls a pair of dice and adds up his or her points. Whoever reaches 100 points first, wins. If a player rolls a 1, he or she loses all point

  • Q : Statistics math Detailed explanation of

    Detailed explanation of requirements for Part C-1 The assignment states the following requirement for Part 1, which is due at the end of Week 4: “Choose a topic from your field of study. Keep in mind you will need to collect at least [sic] 3- points of data for this project. Construct the sheet y

  • Q : Define Well-formed formulas or Wffs

    Wffs (Well-formed formulas): These are defined inductively by the following clauses:    (i) If  P  is an n-ary predicate and  t1, …, tn are terms, then P(t1, …, t

  • Q : Examples of groups Examples of groups:

    Examples of groups: We now start to survey a wide range of examples of groups (labelled by (A), (B), (C), . . . ). Most of these come from number theory. In all cases, the group axioms should be checked. This is easy for almost all of the examples, an

  • Q : Who derived the Black–Scholes Equation

    Who derived the Black–Scholes Equation?

  • Q : Area Functions & Theorem Area Functions

    Area Functions 1. (a) Draw the line y = 2t + 1 and use geometry to find the area under this line, above the t - axis, and between the vertical lines t = 1 and t = 3. (b) If x > 1, let A(x) be the area of the region that lies under the line y = 2t + 1 between t

  • Q : Statistics Caterer determines that 37%

    Caterer determines that 37% of people who sampled the food thought it was delicious. A random sample of 144 out of population of 5000. The 144 are asked to sample the food. If P-hat is the proportion saying that the food is delicious, what is the mean of the sampling distribution p-hat?

  • Q : Ordinary Differential Equation or ODE

    What is an Ordinary Differential Equation (ODE)?