How are relationships between tables implemented?

How are relationships between tables implemented?

• A. Through common columns
• B. Through data encryption
• C. Through stored procedures
• D. Through triggers

Answer: (A)

Relationships in a relational database are established by linking rows through common columns that hold related keys. The typical pattern is to have a primary key in one table and a foreign key in another that references that key, creating a shared set of values that connect the two tables. This shared or common column structure enables meaningful joins and ensures referential integrity, so related records in different tables can be associated accurately. The other options don’t define how tables relate. Encryption protects data, not the way tables link to one another. Stored procedures are blocks of code for performing tasks, not the mechanism that defines relationships. Triggers are actions that run in response to changes, which can enforce rules but don’t establish the fundamental connections between tables.

Relationships in a relational database are established by linking rows through common columns that hold related keys. The typical pattern is to have a primary key in one table and a foreign key in another that references that key, creating a shared set of values that connect the two tables. This shared or common column structure enables meaningful joins and ensures referential integrity, so related records in different tables can be associated accurately.

The other options don’t define how tables relate. Encryption protects data, not the way tables link to one another. Stored procedures are blocks of code for performing tasks, not the mechanism that defines relationships. Triggers are actions that run in response to changes, which can enforce rules but don’t establish the fundamental connections between tables.