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

Area, #What is an easy way to find the area of any figure

#What is an easy way to find the area of any figure

If field of his patio is 195 what is the length of diagonal, Patrick has a ...

Patrick has a rectangular patio whose length is 5 m less than the diagonal and a width which is 7 m less than the diagonal. If the field of his patio is 195 m 2 , what is the lengt

Unconditional and conditional probability, Two events A and B are ind...

Two events A and B are independent events if the occurrence of event A is in no way related to the occurrence or non-occurrence of event B. Likewise for independent

Trigonometry, if theta is a positive acute angle and 2sin theta +15cos squ...

if theta is a positive acute angle and 2sin theta +15cos square theta=7 then find the value of cot theta

Linear programming Special purpose of algorithm, the conclusion about stepp...

the conclusion about stepping stone method in real life situation?

Calculate the regular monthly payments, A washing machine, cash price $ 850...

A washing machine, cash price $ 850 is available on the following terms: A deposit of $ 100 followed by equal payments at the end of each month for the next 18 months, if intere

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