How do I send a query to get the sum of the two tables?

Question

I want to get the sum of the two tables.

1-1.hospital_payment_data table

1-2.hospital_payment_data table data

2-1.advenced_payment table

2-2 advenced_payment table data

I want result

However, sending the query as follows results.

SELECT  COUNT(IF(treatment_fees_check_division = '선수금',
                        treatment_fees_check_division, NULL)) AS COUNT,
        SUM(CASE WHEN treatment_fees_check_division = '선수금'
                   THEN treatment_fees_difference END) + SUM(advenced_amount
             ) AS if_treatment_fees_check_division,
        SUM(advenced_amount) AS sum_init_amount
    FROM  
    (
        SELECT  treatment_fees_check_division, treatment_fees_difference,
                init_amount, advenced_amount
            FROM  hospital_payment_data , advenced_payment 
    )AS a 

bad result

How do I fix the query? I'd like your posture, please.

Answer 1

Is this what you are looking for?

SELECT ( SELECT SUM(...) FROM t1 ... ) +
       ( SELECT SUM(...) FROM t2 ... )  AS sum_of_tables