search
Log In
0 votes
161 views

A.dep-->>job

B.dep-->>part

C.both a and b

D.none of these

in Databases 161 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.

Related questions

1 vote
0 answers
1
131 views
How to find all mvd's in this table.i know mvd defination according to that we let t1,t2,t3,t4 in table but in this table ,which tuple we take t1,t2,t3,t4 .and how defination of.mvd constraints satisfy
asked May 6, 2016 in Databases Sourabh Kumar 131 views
0 votes
1 answer
3
534 views
Multi Valued Dependencies(MVD) satisfied by relation R(A,B,C) with tuples: (a1,b1,c1),(a1,b1.c2), (a2,b1,c1), (a2,b1,c3) A⇢⇢B B⇢⇢A, BC⇢⇢A, B⇢⇢AC
asked Jul 4, 2016 in Databases gate_forum 534 views
31 votes
3 answers
4
4.6k views
Consider the following implications relating to functional and multivalued dependencies given below, which may or may not be correct. if $A \rightarrow \rightarrow B$ and $A \rightarrow \rightarrow C$ then $A \rightarrow \rightarrow BC$ if $A \rightarrow B$ and $A \rightarrow C$ then ... $A \rightarrow \rightarrow C$ Exactly how many of the above implications are valid? $0$ $1$ $2$ $3$
asked Oct 30, 2014 in Databases Ishrat Jahan 4.6k views
...