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

Calculate the area and perimeter of a square, Calculate the area and perime...

Calculate the area and perimeter of a square: Calculate the area and perimeter of a square with w = 5´ and l = 6´.  Be sure to involved units in your answer. Solution:

Number theory, show that all primes except 2, are of the form 4n-1 or 4n+1...

show that all primes except 2, are of the form 4n-1 or 4n+1.

Proof of limit comparison test - sequences and series, Proof of Limit Compa...

Proof of Limit Comparison Test As 0  Now, as   we know that for large enough n the quotient a n /b n should be close to c and thus there must be a positive integer

Decmals, just want to go over it

just want to go over it

What is the probability that the integer chosen is divisible, An integer i...

An integer is chosen at random from the first two hundreds digit. What is the probability that the integer chosen is divisible by 6 or 8.                    (Ans : 1/4 ) Ans:

Numerical methods, Consider the following interpolation problem: Find a q...

Consider the following interpolation problem: Find a quadratic polynomial p(x) such that p(x0) = y0 p’(x1) = y’1 , p(x2) = y2 where x0 is different from x2 and y0, y’1 , y2 a

Discount, outdoor grill- regular price:$360 discount:33 1/3%

outdoor grill- regular price:$360 discount:33 1/3%

Examining a related problem, how to explain this strategy? how to do this s...

how to explain this strategy? how to do this strategy in solving a problem? can you give some example on how to solve this kind of strategy.

Find out the next number 320, Find out the next number in the subsequent pa...

Find out the next number in the subsequent pattern. 320, 160, 80, 40, . . . Each number is divided by 2 to find out the next number; 40 ÷ 2 = 20. Twenty is the next number.

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