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

Interpretations of definite integral, Interpretations of Definite Integral ...

Interpretations of Definite Integral There are some quick interpretations of the definite integral which we can give here. Firstly, one possible interpretation of the defini

Point, what will be the activity of the above said title

what will be the activity of the above said title

What is equivalent of this temperature in degrees fahrenheit, The temperatu...

The temperature in Hillsville was 20° Celsius. What is the equivalent of this temperature in degrees Fahrenheit? This problem translates to the expression 3 {[2 - (-7 + 6)] + 4

Calculate plurality based on the number of voters and candid, Consider an e...

Consider an election with 721 voters. A) If there are 5 candidates, at least x votes are needed to have a plurality of the votes. Find x. B) Suppose that at least 73 votes are n

Example of log rules, Example of Log Rules: Y = ½ gt 2 where g = 32 ...

Example of Log Rules: Y = ½ gt 2 where g = 32 Solution: y = 16 t 2 Find y for t = 10 using logs. log y = log 10     (16 t 2 ) log 10 y = log 10 16 + log 10

Hydrostatic pressure and force - applications of integrals, Hydrostatic Pre...

Hydrostatic Pressure and Force - Applications of integrals In this part we are going to submerge a vertical plate in water and we wish to know the force that is exerted on t

Compute steady state value of capital - solow growth model, Consider the So...

Consider the Solow growth model as given in the lecture notes using the Cobb-Douglas production function Y t = AK 1-α t L α t a) Set up the underlying nonlinear differen

Multiply the polynomials, Multiply following. (a) (4x 2 -x)(6-3x) (b)...

Multiply following. (a) (4x 2 -x)(6-3x) (b) (2x+6) 2 Solution  (a) (4x 2 - x )(6 - 3x ) Again we will only FOIL this one out. (4x 2  - x )(6 - 3x) = 24x 2 -

4.4238/[1.047+{1.111*[9.261/7.777]}*1.01, Ask question #Min 4.4238/[1.047+{...

Ask question #Min 4.4238/[1.047+{1.111*[9.261/7.777]}*1.01

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