Ques: (i) Given an instance of a relation R where A and B are two of...

Ques: (i) Given an instance of a relation R where A and B are two of the attributes in R, describe an algorithm that checks whether a functional dependency A → B holds on R.

(ii) Given a relation with schema R(A, B, C, D, E) and a set of FD's F = {AD → E, AB → C, C → D, E → B} Find a lossless join decomposition to decompose R into collections of relations that are in BCNF

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venereology answered 3 hours ago

Given two sets of data, A and B. i) Data set A has an r value...

Given two sets of data, A and B. i) Data set A has an r value of -.81 and data set B has an r value of .94 Describe the differences between the two data sets as completely as you can using the regression information we have learned. ii) Which linear regression equation, the one for A or the one for B, would probably be a better predictor? Why?

QUERY PROCESSING JOIN 1) Let the schema of a relation r as R(A,B,C), and a relation...

QUERY PROCESSING JOIN 1) Let the schema of a relation r as R(A,B,C), and a relation s has schema S(C,D,E). Relation table r has 40K tuples, relation s has 60K tuples. The block factor of r is 25. The block factor of s is 30. Let the average seek time is t S and average block transfer time is t T . Assume you have a memory that contains M pages, but M< 40K/25 (indicating that s cannot be entirely...

Show that the given relation R is an equivalence relation on set S. Then describe the...

Show that the given relation R is an equivalence relation on set S. Then describe the equivalence class containing the given element z in S, and determine the number of distinct equivalence classes of R. Let S be the set of all possible strings of 3 or 4 letters, let z = ABCD and define x R y to mean that x has the same first letter as y and also the same third letter as y.

Is the relation R consisting of all ordered pairs (a, b) such that a and b...

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Let A and B be sets, and let R be a relation from A to B....

Let A and B be sets, and let R be a relation from A to B. Prove that Rng(R^-1) = Dom(R)

Let R be the relation on Z+× Z+ such that (a, b) R (c, d) if...

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Given the following relation, { ( A, A ), ( A, B ), ( A, D...

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Let R be the relation on the set of people given by aRb if a and...

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Show that the relation 'a R b if and only if a−b is an even integer defined on the Z of integers is an equivalence relation.

S = Z (integers), R = {(a,b) : a = b mod 5}. Is this relation...

S = Z (integers), R = {(a,b) : a = b mod 5}. Is this relation an equivalence relation on S? S = Z (integers), R = {(a,b) : a = b mod 3}. Is this relation an equivalence relation on S? If so, what are the equivalence classes?

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