Question: Given a relational schema R ( A , B , C , D ) , A - > - > BC does not logically imply

Given a relational schema R(A, B, C, D), A ->-> BC does not logically imply A ->-> B (this is true for FDs, but not for MVDs). Construct an example to illustrate this (i.e., a relation instance where the former holds, but the latter doesn't).

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 Databases Questions!

Q:

Schema Design by Decomposition Problem-1: For each of the following collection of relations and functional dependencies, determine if relation(s) is/are in BCNF. If not, then decompose it into a set...

Q:

This is how we have to do it according to the slides: Question 1 Given is the relational schema R= (A, B, C, D, E) and the set of functional dependencies F = {AB BC, C + A, ABC + D). Is R in BCNF? If...

Q:

This is how we have to do it!: Question 3 Given is the relational schema R= (A, B, C, D, E) and the set of functional dependencies F = {AB BC, C + A,BC D}. Is R in 3NF? If not, give a lossless and...

Q:

The relational scheme R (A, B, C, D) and the functional dependencies A B are given; B C Which of the following alternatives is correct? Select one or more: a. A C b. ACD B c. AC B d. AD BC e. A BC...

Q:

This is how we have to do it!: Question 2 Given is the relational schema R= (A, B, C, D, E) and the set of functional dependencies F = {AB BC,C A, ABC D}. Is R in 3NF? If not, give a lossless and...

Q:

Question 3 Given is the relational schema R= (A, B, C, D, E) and the set of functional dependencies F = {AB BC, C + A,BC D}. Is R in 3NF? If not, give a lossless and dependency preserving decom-...

Q:

Question 2 Given is the relational schema R= (A, B, C, D, E) and the set of functional dependencies F = {AB BC, C+ A, ABC D}. Is R in 3NF? If not, give a lossless and dependency preserving decom-...

Q:

Discuss the normal forms for a relational database schema. What does functional dependency mean? Given is the relational schema R( A, B, C, D, E ) as well as the functional dependencies AC BDE B D A...

Q:

Given a relation schema R = { A , B , C , D , E , H } and a set of functional dependencies F = { A B , BC D , A C , E A , A E } , the options for a lossless join decomposition of R are: R 1 = { A , B...

Q:

1. Consider the following instance: A B C D 4 2 5 2 5 8 4 4 3 3 3 4 1 2 5 3 6 4 6 1 - Does the functional dependency D->C hold in this instance? - Does the functional dependency C->B hold in this...

Q:

Several managers in your company are experiencing personal financial problems and have asked that your company switch from LIFO to FIFO so that they can receive bigger bonuses, which are tied to the...

Q:

What are some of the factors that influence the cost of making a weldment?

Q:

Sum the Present Values to Get Total PV of NCF: Calculate each PV and sum them up with the terminal value

Q:

8. Which of the following statements correctly describe the factors that influence the development of skin cancer in individuals? Select all that apply. 1. Tanning in a tanning bed is a safe way to...

Q:

Economist John Taylor has suggested that the Fed use the following rule for choosing its target for the federal funds interest rate (r): r = 2% + + 12 (y y*) / y* + 12 ( *), where is the average...

Q:

Suppose banks install automatic teller machines on every block and, by making cash readily available, reduce the amount of money people want to hold. a. Assume the Fed does not change the money...

Q:

Consider two policiesa tax cut that will last for only 1 year and a tax cut that is expected to be permanent. Which policy will stimulate greater spending by consumers? Which policy will have the...