Polynomial time algorithm - first order query, Mathematics

Assignment Help:

For queries Q1 and Q2, we say Q1 is contained in Q2, denoted Q1 ⊆ Q2, iff Q1 (D) ⊆ Q2(D) for every database D.

  • The container problem for a fixed Query Q0 is the following decision problem: Given a query Q, decide whether Q0 ⊆ Q.
  • The containee problem for a fixed query Q0 is the following decision problem: Given a query Q, decide whether Q ⊆ Q0.

Formally prove or disprove the following statements:

(a) For every conjunctive query Q0, there is a polynomial-time algorithm to decide the container problem for Q0 and for given conjunctive queries Q.

(b) For every conjunctive query Q0, there is a polynomial-time algorithm to decide the container problem for Q0 and for given conjunctive queries Q that can be obtained from Q0 by adding some atoms.

(c) For every conjunctive query Q0, there is a polynomial-time algorithm to decide the containee problem for Q0 and for given conjunctive queries Q.

(d) For every first-order Query Q0, there is an algorithm to decide the containee problem for Q0 and for given first-order queries Q. To prove a statement, sketch an algorithm, along with an argument why it is polynomial, if possible. To disprove it, provide an M-hardness or undecidability proof.


Related Discussions:- Polynomial time algorithm - first order query

Cycloid - parametric equations and polar coordinates, Cycloid The param...

Cycloid The parametric curve that is without the limits is known as a cycloid.  In its general form the cycloid is, X = r (θ - sin θ) Y = r (1- cos θ)  The cycloid pre

One-to-one correspondence to developing pre-number concepts, One-to-one Cor...

One-to-one Correspondence :  Suppose you are given a certain number of cups and saucers, and are asked to find out whether there are enough saucers for all the cups. How would you

How to multiply two fractions, Q. How to Multiply two Fractions? Multip...

Q. How to Multiply two Fractions? Multiplying fractions is really easy! The rule is: "multiply across"- You multiply the numerators, and you multiply the denominators.

What is the probability that the card is a queen, Five cards - the ten, jac...

Five cards - the ten, jack, queen, king and ace, are well shuffled with their face downwards. One card is then picked up at random. (i)  What is the probability that the card is

Help with 7th grade home work, I need help finding a answer of my kids home...

I need help finding a answer of my kids homework because I have no clue.. can you please help me

Introduction To Numerical Methods & Matlab, Can you help me with the course...

Can you help me with the coursework i have in Matlab?

Prove the parallelogram circumscribing a circle is rhombus, Prove that the ...

Prove that the parallelogram circumscribing a circle is rhombus. Ans   Given : ABCD is a parallelogram circumscribing a circle. To prove : - ABCD is a rhombus or AB

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd