The Gateway to Computer Science Excellence
0 votes
130 views

A.dep-->>job

B.dep-->>part

C.both a and b

D.none of these

in Databases by Active (1.5k points) | 130 views
0

Answer is C: Both A and B.

Look at this example. and Read this article

0
But they give answer as d.none of these bcz of last 2 tuples
0
@Saurabh Read the article. If you get something different then let me know. If its correct then mark it as best answer:P :P
0
I think department -->> part
0
Yeah that is the video on YouTube I saw

But I am still in doubt is it correct or not
0
i guess it is correct ...
0

Why the last 2 tuples create problem in mvd

0
becoz it does not follow the constraint or properties of multivalued dependency (x-->-->y)...

which is , if 2 tuples t1 and t2 exist in r relation such that t1(x)= t2(x) then 2 tuples t3 and t4 should also exist  in r with

1) t3(x)=t4(x) =t2(x)=t1(x)

2)t3(y)= t1(y) and t4(y)=t2(y)

3) t3(z)=t2(z) and t4(z)=t1(z)

now in following question  for x= d3 there is only 2 tuple say t1 and t2 , there should be t3 and t4  but not exist here thats why last tuples does not follow the properties .
0

Sonam,how many mvd's and what are they.

I am confusing in this table which tuple I take t1,t2t3,t4 and which attribute I assume x,y,z

Please log in or register to answer this question.

Quick search syntax
tags tag:apple
author user:martin
title title:apple
content content:apple
exclude -tag:apple
force match +apple
views views:100
score score:10
answers answers:2
is accepted isaccepted:true
is closed isclosed:true
50,741 questions
57,251 answers
198,057 comments
104,685 users