Question

A __ is any key that uniquely identifies each row?

1) Primary Key
2) Foreign Key
3) Composite Key
4) Unique Key

Answer 1

A key that uniquely identifies each row in a database table is called a Primary Key. It ensures there are no duplicate rows and maintains data integrity. The Primary Key is one of several key types used in databases.

Step-by-step explanation:

An attribute that uniquely identifies each row in a database table is known as a Primary Key. A Primary Key has a unique value for each row, ensuring that no two rows can have the same Primary Key. This is essential for maintaining data integrity and allows for efficient data retrieval and manipulation. There are other key types as well:

• Foreign Key - a key used to link two tables together.
• Composite Key - a combination of two or more columns in a table that can be used to uniquely identify each row in a table when the single column is not enough to do so.
• Unique Key - a key that can uniquely identify a row in a table, similar to a Primary Key; however, unlike a Primary Key, it can accept one null value and can be more than one in a table.

So, the correct answer to the question is 1) Primary Key.