Question

I have four tables in my database:

• student : contain the student’s ID and name, etc.
• student_fee : contains the paid_date, student_id and fee_id with references to the student and fee tables
• fee : contains the fee_id, fee amount, fee_typeid (ref to fee_type table)
• fee_type : contain the fee_typeid and type of fees – admission fee, monthly tuition fee, fines, uniform fees, etc.

How do I display the students who have already paid the admission fee (or fee_typeid for admission fee) and those who have not paid it?

Well .. English is not my first language 😉

Answer 1

SELECT * FROM student WHERE student_id IN
    (
        SELECT student_id FROM student_fee WHERE fee_id IN
            (
                 SELECT fee_id FROM fee WHERE fee_typeid=?
            )
    )

I believe this is what you need. This is a method of doing joins without actually writing the join syntax.

Basically, you are selecting all the fee_id where they are of the type that you want. Then, you are selecting all the student_id where the fee_id matches the ones you just selected. Finally, you pull all the information about the students whose student_id is one of the ids you just pulled.