Contents
- 1 Which functional dependency is a relationship between or among?
- 2 What is functional dependency that is satisfied by all relations called?
- 3 Why do we need functional dependency?
- 4 Which is the process of breaking a relation into multiple relations?
- 5 When to break up a table for functional dependency?
- 6 When does a multivalued dependency exist in a relation?
Which functional dependency is a relationship between or among?
Explanation. Answer : Attributes. In general, an attribute is a characteristic.
What is functional dependency that is satisfied by all relations called?
Functional dependencies are called trivial if they are satisfied by all relations.
Is a relation between or among the attributes?
A functional dependency is a relationship between or among attributes.
Why do we need functional dependency?
Functional Dependency (FD) is a constraint that determines the relation of one attribute to another attribute in a Database Management System (DBMS). Functional Dependency helps to maintain the quality of data in the database. It plays a vital role to find the difference between good and bad database design.
Which is the process of breaking a relation into multiple relations?
E.F. Codd developed the normalization process in the which early: a….Online Test.
| 119. | Which is the process of breaking a relation into multiple relations: |
|---|---|
| b. | Database modeling |
| c. | Normalization |
| d. | Decomposition |
Which is the best definition of functional dependency?
Definition – What does Functional Dependency mean? Functional dependency is a relationship that exists when one attribute uniquely determines another attribute. If R is a relation with attributes X and Y, a functional dependency between the attributes is represented as X->Y, which specifies Y is functionally dependent on X.
When to break up a table for functional dependency?
It is a rule that suggests if you have a table that appears to contain two entities which are determined by the same primary key then you should consider breaking them up into two different tables. It is displayed on the right side of the functional dependency diagram.
When does a multivalued dependency exist in a relation?
A multivalued dependency exists when there are three attributes A, B, and C in a relation R such that for each value of A the set of B values associated with the A value are independent of the set of C values associated with the A value. We say A multidetermines B and A multidetermines C.
How is the transitive rule related to functional dependency?
Transitivity rule: This rule is very much similar to the transitive rule in algebra if x -> y holds and y -> z holds, then x -> z also holds. X -> y is called as functionally that determines y.