POSTGRESQL DATABASE INTERVIEW QUESTIONS

What does the COUNT function do in PostgreSQL?

Can you explain how the SUM function works in PostgreSQL?

What is the purpose of the AVG function in PostgreSQL?

How would you use the MIN function in PostgreSQL?

Explain the MAX function and its use in PostgreSQL.

What is the difference between COUNT(*) and COUNT(column_name) in PostgreSQL?

How can you use the COUNT function with a GROUP BY clause in PostgreSQL?

Describe a scenario where you would use the SUM function with a HAVING clause in PostgreSQL.

How can you combine the AVG function with window functions in PostgreSQL?

In a PostgreSQL certification exam, you might be asked: Explain the importance of using aggregate functions like COUNT, SUM, AVG, MIN, and MAX in database optimization. Provide an example scenario.