When a relation is said to be a binary relation?

When a relation is said to be a binary relation?

A binary relation is the most studied special case n = 2 of an n-ary relation over sets X1., Xn, which is a subset of the Cartesian product. , in which each prime p is related to each integer z that is a multiple of p, but not to an integer that is not a multiple of p.

Is it possible that all relations can be function Why or why not?

All functions are relations, but not all relations are functions. A function is a relation that for each input, there is only one output. Here are mappings of functions. The domain is the input or the x-value, and the range is the output, or the y-value.

Can you have a function that is not a relation explain?

If you think of the relationship between two quantities, you can think of this relationship in terms of an input/output machine. If there is only one output for every input, you have a function. If not, you have a relation. Relations have more than one output for at least one input.

How do you prove that a function is not a function?

A relation is a function if for each value of x (the independent variable) there is only one possible value of y (the dependent variable). For example, x^2+y^2=4 is NOT a function since choosing an x value of , say 0, results in 2 possible y values : 2 or -2.

How do you show that a relation is binary?

We can visualize a binary relation R over a set A by drawing the elements of A and drawing a line between an element a and an element b if aRb is true. We can visualize a binary relation R over a set A by drawing the elements of A and drawing a line between an element a and an element b if aRb is true.

How we can find binary relation?

Formally, a binary relation from set A to set B is a subset of A X B. For any pair (a,b) in A X B, a is related to b by R, denoted aRb, if an only if (a,b) is an element of R.

Why it is said that all functions are relation but not all relations are function?

In fact, every function is a relation. However, not every relation is a function. In a function, there cannot be two lists that disagree on only the last element. This would be tantamount to the function having two values for one combination of arguments.

Is every relation also a function?

Note: Every relation is not a function. Every function is a relation.

How do you prove that a function is not one to one?

If some horizontal line intersects the graph of the function more than once, then the function is not one-to-one. If no horizontal line intersects the graph of the function more than once, then the function is one-to-one.

What is a binary relation?

More generally, a binary relation is simply a set of ordered pairs. Definition: Let X and Y be sets. A binary relation between members of X and members of Y is a subset of X ×Y — i.e., is a set of ordered pairs (x,y) ∈ X ×Y.

Which binary relations are always in BCNF?

Both A->B and B->A holds. In this case there are two keys {CK = A and B} and relation satisfies BCNF. Hence, every Binary Relation (A relation with two attributes) is always in BCNF! Thanks for contributing an answer to Stack Overflow!

What are the possible functional dependencies on a relation with two attributes?

Consider all the possible sets of (non-trivial) functional dependencies on a relation with two attributes R(A1, A2): 1. A1 -> A2 this means that A1is a key (since from A1 -> A2we can derive that A1->A1A2), and the BCNF condition is satisfied since each dependency has a superkey as determinant;

Does 3rd normal form and non key attribute functionally determine key attribute?

As per my understanding, if for a relation we have 3rd normal form and one non key attribute functionally determine key attribute, it violates the BCNF. Say my relation consists of two attributes A1,A2 Scenario1(only one functional dependency) A1 -> A2 (so A1 is the key, and A2 does not FD A1 : so no violation)