mysql查询通过检查另一个表中的其他两个属性来从一个表中选择所有数据

Question

I have two (2) tables in one database, I want to display all members that are not paid for either payment:

I tried this but not working:

SELECT members.*, payments.amount='', paid_for='fee';

Table 1 "members" with ID, ROLL NO and NAMES

Table 2 "payments" with ID ROLL NO, AMOUNT, PAID_FOR, DATE, STATUS, RECEIPT NO

I want to select all where AMOUNT is empty , PAID FOR fee

That means if there no payment made, it display all members in database as not paid.

Answer 1

Something like this:

SELECT m.ID,m.ROLL_NO,m.NAMES,p.AMOUNT,p.PAID_FOR,p.DATE,p.STATUS,p.RECEIPT_NO

       FROM MEMBERS m  INNER JOIN PAYMENTS p

                 ON m.ROLL_NO = p.ROLL_NO

       WHERE (m.AMOUNT IS NULL OR m.AMOUNT='') AND p.PAID_FOR='fee'

       GROUP BY m.NAMES;