Question

What name is used to denote a common field that exists between two tables, but is also the primary key for one of the tables??"

a. duplicate key
b. foreign key
c. composite primary key
d. distinct key

Answer 1

b. foreign key

Step-by-step explanation:

In the database world, a foreign key is a field on one table and a primary key for another table. The purpose of a foreign key is to provide linkages between two or more tables. Given two tables A and B, and making A the point of reference, a primary key is a field that is unique in A while a foreign key is unique in B.

On another hand, a composite primary key is a combination of two or more fields/columns on database table that can be used to uniquely identify each row in the table.

In the database lingua, what we have is a unique key not a distinct key, though the two words are similar in meaning.

A duplicate key is used when an information may be repeatedly entered on a table.

So the correct option is a foreign key.