MySQL 8.0

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create TABLE `tenantmadeutilitypayment` (
  `Receipt_id` int not null AUTO_INCREMENT,
  `DateOfPay` date,
  `PersonalAccount` int unsigned DEFAULT NULL,
  `Payment_id` int unsigned NOT NULL,
  `Paid_UAH` decimal(5,2) DEFAULT NULL,
-- FOREIGN KEY (PersonalAccount) REFERENCES Tenants (PersonalAccount),
-- FOREIGN KEY (Payment_id) REFERENCES TypesOfUtilityPayments (Payment_id),
  PRIMARY KEY (`Receipt_id`));
CREATE TRIGGER add_penalty
BEFORE INSERT
ON tenantmadeutilitypayment
FOR EACH ROW
SET NEW.Paid_UAH = NEW.Paid_UAH * (1 + CASE WHEN DAY(NEW.DateOfPay) > 15 
                                            THEN (DAY(NEW.DateOfPay) - 15) * 0.005
                                            ELSE 0
                                            END);
INSERT INTO tenantmadeutilitypayment (Receipt_id, DateOfPay, Paid_UAH, Payment_id, PersonalAccount)
    VALUES
    ('001','2020-09-03','38.00','100','44098'),
    ('002','2020-10-05','45.47','101','44099'),
    ('003','2020-08-21','36.50','102','44100'),
    ('004','2020-09-30','37.43','103','44101'),
    ('005','2020-09-28','39.36','104','44102'),
    ('006','2020-09-03','39.00','105','44103'),
    ('007','2020-10-07','25.00','106','44104'),
    ('008','2020-11-09','50.98','107','44105'),
    ('009','2020-09-10','40.40','108','44106'),
    ('010','2020-08-13','33.76','109','44107'),
    ('011','2020-10-23','29.66','110','44108'),
    ('012','2020-11-24','38.00','111','44109'),
    ('013','2020-09-26','24.00','112','44110'),
    ('014','2020-09-15','38.50','113','44111'),
    ('015','2020-08-15','40.00','114','44112');
SELECT * FROM tenantmadeutilitypayment


Receipt_id
DateOfPay
PersonalAccount
Payment_id
Paid_UAH


1
2020-09-03
44098
100
38.00

2
2020-10-05
44099
101
45.47

3
2020-08-21
44100
102
37.60

4
2020-09-30
44101
103
40.24

5
2020-09-28
44102
104
41.92

6
2020-09-03
44103
105
39.00

7
2020-10-07
44104
106
25.00

8
2020-11-09
44105
107
50.98

9
2020-09-10
44106
108
40.40

10
2020-08-13
44107
109
33.76

11
2020-10-23
44108
110
30.85

12
2020-11-24
44109
111
39.71

13
2020-09-26
44110
112
25.32

14
2020-09-15
44111
113
38.50

15
2020-08-15
44112
114
40.00

Receipt_id	DateOfPay	PersonalAccount	Payment_id	Paid_UAH
1	2020-09-03	44098	100	38.00
2	2020-10-05	44099	101	45.47
3	2020-08-21	44100	102	37.60
4	2020-09-30	44101	103	40.24
5	2020-09-28	44102	104	41.92
6	2020-09-03	44103	105	39.00
7	2020-10-07	44104	106	25.00
8	2020-11-09	44105	107	50.98
9	2020-09-10	44106	108	40.40
10	2020-08-13	44107	109	33.76
11	2020-10-23	44108	110	30.85
12	2020-11-24	44109	111	39.71
13	2020-09-26	44110	112	25.32
14	2020-09-15	44111	113	38.50
15	2020-08-15	44112	114	40.00