Question: Let W ( A , B ) and Q ( C , D ) be two relation schemas. Let r 1 and r 2 be

Let W(A, B) and Q(C,D) be two relation schemas. Let r1 and r2 be the corresponding relation instances. B is a foreign key that refers to C in r2. Assuming that all tuples in r1 and r2 satisfy referential integrity constraints, which of the following is ALWAYS TRUE?

Step by Step Solution

There are 3 Steps involved in it

1 Expert Approved Answer
Step: 1 Unlock blur-text-image
Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock
Step: 3 Unlock

Students Have Also Explored These Related Programming Questions!

Q:

I've attached what I have thus far and then the notes that I received back below the questions. I need to prove A1 - A10. Some require specific numeric entries. I attempted this but need to more...

Q:

For the question below, use these symbols correspondingly: Preference relation: ? Strictly preferred to: ? Indifference: ~ Is a subset of: ? i.e. A ? B means A is a subset of B Please bold things...

Q:

ABP C bbprod.hvcc.edu/webapps/assessment/take/take.jsp?course_assessment_id=_96693_1&course_id=_30920_1&content_id=_2130348_1&question_num_1.x=0&togg... LE Free Plagiarism Che... Movierulz | Watch...

Q:

Kindly help me solve these problems A firm uses inputs of labor, L, and capital, K, to produce its output, Q, according to the production function Q=f(X,L)-9LUSKVS. The firm is a price-taker in the...

Q:

Discrete mathematics : 8. Suppose that Rand S are reflexive relations on a set A with |A| = n > 0. State whether following statements are true or false? (1) (points will be given only if all answers...

Q:

Solve all problems. Solve the following 2 period model for equilibrium. Preferences are given as u(c?,c?)=ln(c?)+?*ln(c?), where c? is consumption today and c? is consumption tomorrow, and ? is the...

Q:

Let A, B be sets. Define: (a) the Cartesian product (A B) (b) the set of relations R between A and B (c) the identity relation A on the set A [3 marks] Suppose S, T are relations between A and B, and...

Q:

answer the question clearly You are building a flight-control system for which a convincing safety case must be made. Would you assign the tasks of safety requirements engineering, test case...

Q:

Give Correct ANSWERS Human-Computer Interaction (a) If you had been one of the original inventors of the WIMP interface, and engineers on the technical team had been sceptical about the advantages...

Q:

dee complete please help Complexity Theory (a) Defifine the set of Boolean expressions 2CNF and the language 2SAT over them. (b) For a Boolean expression in 2CNF, let G() be the directed graph with...

Q:

From the water sample analysis: 40 mg/L Ca+2, 5 mg/L Mg+2, 10 mg/L K+, 10 mg/L SO4-2, and alkalinity which is equal to 122 mg/L as CaCO3. Calculate the TH, CH, and NCH. Also check the classification...

Q:

Data pertaining to the current position of Spruce Pine Medical Company are as follows: Cash ............. $384,000 Marketable securities ....... 176,000 Accounts and notes receivable (net) . 608,000...

Q:

1 0 - year 5 % coupon bonds of Cow company are currently selling $ 1 0 8 0 . If these bonds have a $ 1 0 2 0 call option exercisable after 5 years, what is their yield to call ( YTC ) ? 3 . 2 3 % 7 ....

Q:

committed to delivering quality Next-Gen Rangers from our Silverton Assembly Plant and Struandale Engine Plant. (20 Marks) (6marks) Considering the statement above, discuss how each of the followin