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

Weight, if an object weighed 11 pounds how many ounces would it weigh

if an object weighed 11 pounds how many ounces would it weigh

Infinity, Are there more rational numbers than integers?#

Are there more rational numbers than integers?#

Word problem, A jet flew at an average speed of 480mph from Point X to Poin...

A jet flew at an average speed of 480mph from Point X to Point Y. Because of head winds, the jet averaged only 440mph on the return trip, and the return trip took 25 minutes longer

Logs, log4^(x+2)=log4^8

log4^(x+2)=log4^8

Regression, Regression line drawn as y=c+1075x, when x was 2, and y was 239...

Regression line drawn as y=c+1075x, when x was 2, and y was 239, given that y intercept was 11. Caculate the residual

Differance between expanded notation vs. standard notation , Differance bet...

Differance between Expanded Notation vs. Standard Notation ? A number written in expanded notation is broken down into parts just like it is in a place-value table. Example

Index of summation - sequences and series, Index of summation - Sequences a...

Index of summation - Sequences and Series Here now, in the i is termed as the index of summation or just index for short and note that the letter we employ to represent

Implement immutable data type rational for rational number, Implement an im...

Implement an immutable data type Rational for rational numbers that supports addition, subtraction, multiplication and division. public class Rational Ration

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