Consider the relation R(A, B, C, D, E), where it is known that the only keys are {A, C, D} and {D, E}:
Give a set of functional dependencies that will make {A, C, D} and {D, E} be the only keys of R. This set should be such that if you delete any FD, then the keys of R will be something other than {A, C, D} and {D, E}.
Candidate Key:
A candidate key is an attribute or set of attributes that uniquely and minimally identify an entity instance in an entity set or record in a table. In a single table, there may be more than one candidate keys.
Primary Key:
The primary key is one of the selected keys from the list of candidate keys to identify the record uniquely.
Functional Dependency:
It is a relationship between two attributes in which the right-hand side attribute is functionally dependent on the left-hand side attribute.
If the value of attribute Y is determined by the value of X then it is represented as given below:
X → Y
The given relation is:
R(A, B, C, D, E)
The given keys are:
{A,C,D}
{D,E}
As per the given details, the functional dependencies will be as given below:
{A,C,D} -> B
{A,C,D} -> E
{D,E} -> A
{D,E} -> B
{D,E} -> C
Consider the relation R(A, B, C, D, E), where it is known that the only keys...
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