What is the purpose of a foreign key in a relational database?
Practice Questions
1 question
Q1
What is the purpose of a foreign key in a relational database?
To uniquely identify a record
To create a relationship between two tables
To enforce data integrity
All of the above
A foreign key serves to create a relationship between two tables and enforce data integrity by ensuring that the value in one table corresponds to a valid record in another.
Questions & Step-by-step Solutions
1 item
Q
Q: What is the purpose of a foreign key in a relational database?
Solution: A foreign key serves to create a relationship between two tables and enforce data integrity by ensuring that the value in one table corresponds to a valid record in another.
Steps: 5
Step 1: Understand that a relational database consists of multiple tables that can be related to each other.
Step 2: Know that a foreign key is a special column in one table that links to the primary key of another table.
Step 3: Realize that the primary key is a unique identifier for records in its own table.
Step 4: Learn that the foreign key ensures that the value in the foreign key column matches a value in the primary key column of the other table.
Step 5: Understand that this relationship helps maintain data integrity, meaning it prevents invalid data from being entered.
