Functional dependency: An association between two attributes or two set of attributes in a same relational database table which is having some constraints is known as functional dependency. In a table, one attribute is functionally dependent on another attribute to take one value. For example: Consider that if Column A uniquely identifies the Column B of the same table then it is represented as which means that “B” is functionally dependent on “A”. Let assume that the student table contains the attributes such as “stud_id”, “stud_name” and “stud_age”. From this table, the “stud_id” attribute can uniquely identifies the “stud_name” attribute because the student can easily represent the student name associated with it. Here, the attribute “stud_name” is functionally depend upon the attribute of “stud_id”. Determinant: In a database, determinant is a type of attribute which is used to determine the values assigned to other attributes located in the same row of a table. In functional dependency between two attributes, the attribute on the left hand side is determinant and the attribute on the right hand side is determined. For every value of the determinant there is one and only associated value called determined. For example: If the “A” is the determinant and “B” is the determined then it is true that “A” functionally determines “B”. This can be represented as “ A → B ”.

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Chapter 2, Problem 2.24RQ

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Functional dependency:

An association between two attributes or two set of attributes in a same relational database table which is having some constraints is known as functional dependency.

In a table, one attribute is functionally dependent on another attribute to take one value.

For example: Consider that if Column A uniquely identifies the Column B of the same table then it is represented as which means that “B” is functionally dependent on “A”.

Let assume that the student table contains the attributes such as “stud_id”, “stud_name” and “stud_age”. From this table, the “stud_id” attribute can uniquely identifies the “stud_name” attribute because the student can easily represent the student name associated with it.

Here, the attribute “stud_name” is functionally depend upon the attribute of “stud_id”.

Determinant:

In a database, determinant is a type of attribute which is used to determine the values assigned to other attributes located in the same row of a table.

In functional dependency between two attributes, the attribute on the left hand side is determinant and the attribute on the right hand side is determined.

For every value of the determinant there is one and only associated value called determined.

For example: If the “A” is the determinant and “B” is the determined then it is true that “A” functionally determines “B”. This can be represented as “ A→B ”.

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