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

Retail price index, Retail price index This is weighted average of pri...

Retail price index This is weighted average of price relatives based on an average household in the base year. The items consumed are divided into groups as liker food, transp

Solve the subsequent quadratic equation, Solve the subsequent quadratic equ...

Solve the subsequent quadratic equation: Solve the subsequent quadratic equation through taking the square roots of both sides. 3x 2 = 100 - x 2 Solution: Step 1

Example of graphical technique of linear equations, Explain the Graphical T...

Explain the Graphical Technique of Linear Equations by using this figure.

Definite integral, Definite Integral : Given a function f ( x ) which is c...

Definite Integral : Given a function f ( x ) which is continuous on the interval [a,b] we divide the interval in n subintervals of equivalent width, Δx , and from each interval se

What''s my balance, I should have an account balance for $50.96. You took o...

I should have an account balance for $50.96. You took out $50.96 for a product on 6/18 which was NOT downloaded or delivered as it not available in the time frame I needed it. I am

Matrix inverse, Here we need to see the inverse of a matrix. Provided a squ...

Here we need to see the inverse of a matrix. Provided a square matrix, A, of size n x n if we can get the other matrix of similar size, B that, AB = BA = I n after that we call

Find out a series solution for differential equation, Find out a series sol...

Find out a series solution for the following differential equation about x 0 = 0 y′′ + y = 0.   Solution Note that in this case p(x)=1 and therefore every point is an or

#title.automotive cruise control system., What are some of the interestingm...

What are some of the interestingmodern developments in cruise control systems that contrast with comparatively basic old systems

Marketing, What are the Input and Output of Marketing

What are the Input and Output of Marketing

Maths, what is the diameter of a circle

what is the diameter of a circle

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