MySQL 5.7

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CREATE TABLE `calendar` (
  `date` date DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;



INSERT INTO `calendar` (`date`) VALUES
('2021-06-14'),
('2021-06-15'),
('2021-06-16'),
('2021-06-17'),
('2021-06-18'),
('2021-06-19'),
('2021-06-20'),
('2021-06-21'),
('2021-06-22'),
('2021-06-23'),
('2021-06-24'),
('2021-06-25'),
('2021-06-26'),
('2021-06-27'),
('2021-06-28'),
('2021-06-29'),
('2021-06-30'),
('2021-07-01'),
('2021-07-02'),
('2021-07-03'),
('2021-07-04'),
('2021-07-05'),
('2021-07-06'),
('2021-07-07'),
('2021-07-08'),
('2021-07-09'),
('2021-07-10'),
('2021-07-11'),
('2021-07-12'),
('2021-07-13'),
('2021-07-14');
CREATE TABLE `users_balancemaster` (
  `id` int(11) NOT NULL,
  `user_id` int(11) NOT NULL,
  `credits` decimal(18,8) NOT NULL DEFAULT '0.00000000',
  `debits` decimal(18,8) NOT NULL DEFAULT '0.00000000',
  `wallet_id` int(11) NOT NULL,
  `notes` text,
  `ondate` datetime NOT NULL,
  `current_balance` decimal(18,8) NOT NULL DEFAULT '0.00000000',
  `transaction_type` int(11) DEFAULT NULL COMMENT '1=creditwallet,2=send/receive,3=coinify,4=adminfund',
  `transaction_id` int(11) DEFAULT NULL,
  `status` int(1) NOT NULL DEFAULT '1'
) ENGINE=InnoDB DEFAULT CHARSET=utf8;


INSERT INTO `users_balancemaster` (`id`, `user_id`, `credits`, `debits`, `wallet_id`, `notes`, `ondate`, `current_balance`, `transaction_type`, `transaction_id`, `status`) VALUES
(1, 1, '0.97700707', '0.00000000', 1, 'Purchase 0.97700707 For ZAR 280.03000000', '2021-06-30 05:21:03', '20.95629595', 3, 1, 1),
(2, 1, '1.00000000', '0.00000000', 1, 'received 1.00000000 SAC from 0xf1108EEd73D5cB83C124eA66D67d8E5DcF6C8264 Outside Network', '2021-07-02 10:17:25', '21.95629595', 1, 2, 1),
(3, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC to 0xc2888B6b3E818beBcb840b94007338bbc79568BF', '2021-07-02 11:07:23', '20.95629595', 2, 3, 1),
(4, 14, '1.42046290', '0.00000000', 2, 'Purchase 1.42046290 For ZAR 41.04000000', '2021-07-02 11:40:34', '1.42046290', 3, 4, 1),
(5, 1, '0.92044503', '0.00000000', 1, 'Purchase 0.92044503 For ZAR 26.59000000', '2021-07-02 11:59:15', '21.87674098', 3, 5, 1),
(6, 1, '0.92038577', '0.00000000', 1, 'Purchase 0.92038577 For ZAR 26.59000000', '2021-07-02 12:06:12', '22.79712675', 3, 6, 1),
(7, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 12:24:11', '21.79712675', 2, 7, 1),
(8, 14, '10.00000000', '0.00000000', 2, 'received 10.00000000 SAC from 0xc2888B6b3E818beBcb840b94007338bbc79568BF Outside Network', '2021-07-02 12:37:11', '11.42046290', 3, 8, 1),
(9, 14, '10.00000000', '0.00000000', 2, 'received 10.00000000 SAC from 0xc2888B6b3E818beBcb840b94007338bbc79568BF Outside Network', '2021-07-02 12:37:11', '21.42046290', 3, 9, 1),
(10, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 12:49:25', '20.79712675', 2, 10, 1),
(11, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 13:02:52', '19.79712675', 2, 11, 1),
(12, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 13:05:04', '18.79712675', 2, 12, 1),
(13, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 13:07:14', '17.79712675', 2, 13, 1),
(14, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 13:08:36', '16.79712675', 2, 14, 1),
(15, 14, '1.00000000', '0.00000000', 2, NULL, '2021-07-02 13:08:55', '22.42046290', 2, NULL, 1),
(16, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 13:18:06', '15.79712675', 2, 15, 1),
(17, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 13:19:19', '14.79712675', 2, 16, 1),
(18, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 13:24:32', '13.79712675', 2, 17, 1),
(19, 1, '0.00000000', '1.00000000', 1, 'Sent 1.00000000 SAC Outside Network', '2021-07-02 13:26:51', '12.79712675', 2, 18, 1),
(20, 14, '1.00000000', '0.00000000', 2, 'Received 1.00000000 SAC from kakadiya jay a', '2021-07-02 13:26:59', '23.42046290', 2, 18, 1);


ALTER TABLE `users_balancemaster`
  ADD PRIMARY KEY (`id`),
  ADD KEY `user_id` (`user_id`,`wallet_id`);

ALTER TABLE `users_balancemaster`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT, AUTO_INCREMENT=21;
SELECT
`date`,
IF(balance IS NULL, @balance, @balance := balance) balance
FROM (select c.`date`
,AVG( a.current_balance)  as balance from users_balancemaster a 
RIGHT join calendar c on c.date= date(a.ondate) 
GROUP BY c.date
ORDER BY c.date) t1,(SELECT @balance := 0) t2



date
balance


2021-06-14
0

2021-06-15
0

2021-06-16
0

2021-06-17
0

2021-06-18
0

2021-06-19
0

2021-06-20
0

2021-06-21
0

2021-06-22
0

2021-06-23
0

2021-06-24
0

2021-06-25
0

2021-06-26
0

2021-06-27
0

2021-06-28
0

2021-06-29
0

2021-06-30
20.956295950000

2021-07-01
20.956295950000

2021-07-02
17.929475875263

2021-07-03
17.929475875263

2021-07-04
17.929475875263

2021-07-05
17.929475875263

2021-07-06
17.929475875263

2021-07-07
17.929475875263

2021-07-08
17.929475875263

2021-07-09
17.929475875263

2021-07-10
17.929475875263

2021-07-11
17.929475875263

2021-07-12
17.929475875263

2021-07-13
17.929475875263

2021-07-14
17.929475875263


select c.date
,a.current_balance 
from users_balancemaster a 
RIGHT join calendar c on c.date= date(a.ondate) ,(SELECT @balance := 0) t1
ORDER BY c.date


date
current_balance


2021-06-14
null

2021-06-15
null

2021-06-16
null

2021-06-17
null

2021-06-18
null

2021-06-19
null

2021-06-20
null

2021-06-21
null

2021-06-22
null

2021-06-23
null

2021-06-24
null

2021-06-25
null

2021-06-26
null

2021-06-27
null

2021-06-28
null

2021-06-29
null

2021-06-30
20.95629595

2021-07-01
null

2021-07-02
19.79712675

2021-07-02
18.79712675

2021-07-02
17.79712675

2021-07-02
16.79712675

2021-07-02
22.42046290

2021-07-02
15.79712675

2021-07-02
14.79712675

2021-07-02
21.95629595

2021-07-02
13.79712675

2021-07-02
20.95629595

2021-07-02
12.79712675

2021-07-02
1.42046290

2021-07-02
23.42046290

2021-07-02
21.87674098

2021-07-02
22.79712675

2021-07-02
21.79712675

2021-07-02
11.42046290

2021-07-02
21.42046290

2021-07-02
20.79712675

2021-07-03
null

2021-07-04
null

2021-07-05
null

2021-07-06
null

2021-07-07
null

2021-07-08
null

2021-07-09
null

2021-07-10
null

2021-07-11
null

2021-07-12
null

2021-07-13
null

2021-07-14
null

date	balance
2021-06-14	0
2021-06-15	0
2021-06-16	0
2021-06-17	0
2021-06-18	0
2021-06-19	0
2021-06-20	0
2021-06-21	0
2021-06-22	0
2021-06-23	0
2021-06-24	0
2021-06-25	0
2021-06-26	0
2021-06-27	0
2021-06-28	0
2021-06-29	0
2021-06-30	20.956295950000
2021-07-01	20.956295950000
2021-07-02	17.929475875263
2021-07-03	17.929475875263
2021-07-04	17.929475875263
2021-07-05	17.929475875263
2021-07-06	17.929475875263
2021-07-07	17.929475875263
2021-07-08	17.929475875263
2021-07-09	17.929475875263
2021-07-10	17.929475875263
2021-07-11	17.929475875263
2021-07-12	17.929475875263
2021-07-13	17.929475875263
2021-07-14	17.929475875263

date	current_balance
2021-06-14	null
2021-06-15	null
2021-06-16	null
2021-06-17	null
2021-06-18	null
2021-06-19	null
2021-06-20	null
2021-06-21	null
2021-06-22	null
2021-06-23	null
2021-06-24	null
2021-06-25	null
2021-06-26	null
2021-06-27	null
2021-06-28	null
2021-06-29	null
2021-06-30	20.95629595
2021-07-01	null
2021-07-02	19.79712675
2021-07-02	18.79712675
2021-07-02	17.79712675
2021-07-02	16.79712675
2021-07-02	22.42046290
2021-07-02	15.79712675
2021-07-02	14.79712675
2021-07-02	21.95629595
2021-07-02	13.79712675
2021-07-02	20.95629595
2021-07-02	12.79712675
2021-07-02	1.42046290
2021-07-02	23.42046290
2021-07-02	21.87674098
2021-07-02	22.79712675
2021-07-02	21.79712675
2021-07-02	11.42046290
2021-07-02	21.42046290
2021-07-02	20.79712675
2021-07-03	null
2021-07-04	null
2021-07-05	null
2021-07-06	null
2021-07-07	null
2021-07-08	null
2021-07-09	null
2021-07-10	null
2021-07-11	null
2021-07-12	null
2021-07-13	null
2021-07-14	null