# Database - The Relational Model and Normalization - Discussion

### Discussion :: The Relational Model and Normalization - General Questions (Q.No.1)

1.

Every time attribute A appears, it is matched with the same value of attribute B, but not the same value of attribute C. Therefore, it is true that:

 [A]. A → B. [B]. A → C. [C]. A → (B,C). [D]. (B,C) → A.

Explanation:

No answer description available for this question.

 Abhishek Tamrakar said: (Mar 2, 2011) Beacause only value of A will match with B. So A->B is true.

 Aani said: (Apr 15, 2011) Because of logical signs properties.

 Shrav said: (Jul 5, 2011) A can uniquely identifies B each time so A->B

 Honey said: (Oct 3, 2011) What is it's meaning---- A->B..?

 Runa said: (Feb 3, 2012) A->B means the occurence of A attribute with B eyery time.

 Chandra said: (Mar 1, 2012) A->B every attribute in A should match with B.

 Ouen said: (Mar 27, 2012) Value of B depends on value of A; i.e. A is uniquely determined B

 Khalid Seid said: (Feb 7, 2013) Value of B depends on value of A. i.e A is the determinant but B is the dependent.

 Nivikpr said: (Jul 31, 2013) As per the rule A->B means if A is true then B is true.

 Vishnu said: (Oct 20, 2013) The functional dependency A->B states that the set of values present in A are also in the B so that's why it matches the values in the case of A and B but not with C.

 Richa Chaurasia said: (Apr 2, 2014) Because of every attribute of A will also match with B but not C. And then value of A \$ B will depend to each other. A->B.

 Rahul said: (Apr 26, 2014) A -> B means that, each value of A determines exactly one value of B. And B is functionally dependent on A.

 Shivakavya said: (Nov 12, 2014) Because A can uniquely identifies B each time. So A->B. Option A.

 Kash said: (Dec 12, 2014) It is a general thing to be noticed that if A will be related to both B & C, then how can the value not be same to C. So option A is correct. !

 Rahul Kumar said: (Mar 31, 2015) According to question A->B. That means A would have all the contents such as that of B. So instead of using tends to operation. Here have to use the UNION operation (A U B). And guys please look forward for this.

 Arshad said: (Jul 8, 2015) A is functionally dependent on B.

 Padmasri said: (Jul 9, 2015) Because A can uniquely identifies B each time. As per the rule A->B means if A is true then B is true.

 Harsh Dusane said: (Sep 3, 2015) Because here A functionally determines B but not C so A->B.

 Emil said: (Dec 12, 2015) Is A-->B is same as B-->A. A matches with B, so is it true that B matches with A?

 Sefu Julius said: (Jul 5, 2016) The correct answer is A->B.

 Shahin said: (Feb 28, 2017) @Emil. If A -> B holds then it's not necessary the B -> A also hold true. A B ---------------------------- b 5 b 5 c 5 For every occurrence of b in A there is value 5 in B hence A -> B. But for every Value of B which is 5 is not same value in A (b,c two values in A). Hence If A -> B holds then it's not necessary that B -> A also holds true.

 Elias Joseph said: (Jul 3, 2017) Answer is A because in a change of a implies that also b change.

 Harsha said: (Jun 20, 2019) Because A is functional to B is less than or greater than to it.