Option C (4,24,8)
CREATE TABLE S(B integer , C integer, D integer);
INSERT INTO S VALUES(2,4,6);
INSERT INTO S VALUES(4,6,8);
INSERT INTO S VALUES(4,7,9);
SELECT Sum( B * C) AS SUM,Max(D) AS MAX FROM S GROUP BY B;
Output:
8|6 52|9
Suppose: Relation S(B,C,D) has the following tuples: 68 79 Which of the following tuples is NOT...
Suppose relation R(A, B, C) has the following tuples: and relation S(A, B, C) has the following tuples: Compute the intersection of the relations R and S. which of the following tuples is in the result? (2, 5, 4) (1, 2, 6) (2, 2, 6) (2, 5, 3)
Suppose that we pick the following four tuples from a legal relation S (S has 100 tuples in total). S has the following schema: (A: integer, B: integer, C: integer) The four tuples are: (1,2,3), (4,2,3), (5,3,3) and (5,3,4). Which of the following functional (→)can you infer does not hold over relation S? a. A → B b. BC → A c. A → C d. AC → B
Let R(A,B,C,D) be a relation with FDs F = {A—B, AC, C-A, B,C, ABC-D} Which of the following statements is correct ? (2 points) Select one: G = {A-B, B-C, C-A, AC=D } is a canonical cover of F H = { AC, CA, BC,BD} is a canonical cover of F. o F is a canonical cover of itself. O G and H are canonical covers of F. None of the above.
Suppose that the current instances of relations R(A, B) and S(A, C) have 100 tuples and 200 tuples, respectively. (a) What are the minimum and maximum possible number of tuples in the resulting relation instance of R S. (b) What is your answer to the above question if it is given that attribute A is a key for R. (c) When attribute A is a key for R and A is a foreign key for S referencing R.
Let R(A,B,C,D,E) be a relation with FDs F = {AB-C, CD-E, E-B, CE-A} Consider an instance of this relation that only contains the tuple (1, 1, 2, 2, 3). Which of the following tuples can be inserted into this relation without violating the FD's? (2 points) Select one: O (0, 1, 2, 4,3) (1,1,2,2,4) (1.2.2, 2, 3) o (1,1,3,2,3) All of the above can be inserted. None of the above can be inserted.
Let R(A, B, C, D) be a relation with FDs F= {A->B, A->C,
C->A, B->C, ABC->D} which of the statement is correct?
Question 2 Not yet answered Marked out of 2.00 P Flag question Let R(A,B,C,D) be a relation with FDs F = {AL-B, AC, CA, B-C, ABC-D} Which of the following statements is correct ? (2 Points) Select one: O G = {A--B, BC, C-A, AC-D} is a canonical cover of F OH = {A-C, C+A, B-C, B-D} is...
1) Consider a relation R(A,B) with r tuples, all unique within R, and a relation S(B,C) with s tuples, all unique within S. Let t represent the number of tuples in R natural-join S. What is the value range of t? What is the value of t for R natural-join R (assuming no null values in R)? Explain your answer.
Let R(A, B, C, D, E) be a relation wit FDs F = {AB->C,
CD->E, E->B, CE->A}....
Question 4 Not yet answered Marked out of 2.00 P Flag question Let R(A,B,C,D,E) be a relation with FDs F = {AB-C, CD-E, E-B, CE-A} Consider an instance of this relation that only contains the tuple (1, 1, 2, 2, 3). Which of the following tuples can be inserted into this relation without violating the FD's? (2 points) Select one: 0 (0, 1,...
Question 1 (5 marks) Consider two relations called Item and Orderltem. Imagine that relation Item has 160,000 tuples and Orderltem has 200,000 tuples. Both relations store 100 tuples per a page. Consider the following SQL statement SELECT * FROM Item INNER JOIN OrderItem ON Item.ItemID-OrderItem. ItemID; We wish to evaluate an equijoin between Orderltem and Item, with an equality condition Item.ltemID Orderltem.ItemID. There are 802 buffer pages available in memory for this operation. Both relations are stored as (unsorted) heap...
Let R(A,B,C,D) be a relation with FDs F = {A-B, A-C, C-A, B-C, ABC—D} Which of the following statements is correct ? (2 Points) Select one: G= {A-B, B-C, C-A, AC-D } is a canonical cover of F O H = {A-C, C-A,B,C,B-D) is a canonical cover of F. o F is a canonical cover of itself. G and Hare canonical covers of F. None of the above.