POSTGRESQL DATABASE INTERVIEW QUESTIONS

What is a foreign key in PostgreSQL?

How do you define a foreign key in PostgreSQL when creating a table?

Why are foreign keys important in PostgreSQL databases?

How can you add a foreign key constraint to an existing table in PostgreSQL?

What happens if you try to delete a row in the parent table that is referenced by a foreign key in PostgreSQL?

Explain the purpose of the ON DELETE CASCADE clause in a foreign key definition in PostgreSQL.

How can you use the ON UPDATE CASCADE clause with foreign keys in PostgreSQL?

Describe a scenario where you would use the DEFERRABLE option for a foreign key in PostgreSQL.

How do you drop a foreign key constraint in PostgreSQL?

What are the performance implications of using foreign keys in PostgreSQL?