MySQL 8.0

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Create Table table_name(Date_ TIMESTAMP, transaction_id VARCHAR(50), customer_id INT, product_name VARCHAR(50), qty INT);

Insert Into table_name Values('2022-08-05 10:44:59.000','5-123',888,'A',1),
('2022-08-05 10:44:59.000','5-123',888,'A',1),
('2022-08-05 18:32:22.000','5-179',174,'ZZ',1),
('2022-08-06 10:32:22.000','6-264',223,'QA',1),
('2022-08-06 10:32:52.000','6-264',223,'QB',1),
('2022-08-06 12:57:12.000','6-365',379,'A',1),
('2022-08-07 20:16:38.000','7-974',888,'V',1),
('2022-08-08 17:48:11.000','8-276',732,'R',1),
('2022-08-09 13:29:43.000','9-390',623,'G',1),
('2022-08-10 09:33:57.000','10-862',623,'TT',1),
('2022-08-11 16:23:31.000','11-348',623,'XD',1);
Select T.Date_, T.transaction_id, T.customer_id, T.product_name, T.qty
From table_name T
Where Exists(Select 1 From table_name D 
             Where D.customer_id = T.customer_id And
                   D.transaction_id <> T.transaction_id
             )
And T.Date_ Between '2022-08-01 00:00:00' And '2022-08-31 00:00:00'


Date_
transaction_id
customer_id
product_name
qty


2022-08-05 10:44:59
5-123
888
A
1

2022-08-05 10:44:59
5-123
888
A
1

2022-08-07 20:16:38
7-974
888
V
1

2022-08-09 13:29:43
9-390
623
G
1

2022-08-10 09:33:57
10-862
623
TT
1

2022-08-11 16:23:31
11-348
623
XD
1


Select T.Date_, T.transaction_id, T.customer_id, T.product_name, T.qty
From table_name T
Where Exists(Select 1 From table_name D 
             Where D.customer_id = T.customer_id And
                   D.transaction_id <> T.transaction_id
             )
And DATE_FORMAT(Date_, '%Y-%m') ='2022-08'


Date_
transaction_id
customer_id
product_name
qty


2022-08-05 10:44:59
5-123
888
A
1

2022-08-05 10:44:59
5-123
888
A
1

2022-08-07 20:16:38
7-974
888
V
1

2022-08-09 13:29:43
9-390
623
G
1

2022-08-10 09:33:57
10-862
623
TT
1

2022-08-11 16:23:31
11-348
623
XD
1

`Date_`	`transaction_id`	`customer_id`	`product_name`	`qty`
`2022-08-05 10:44:59`	`5-123`	`888`	`A`	`1`
`2022-08-05 10:44:59`	`5-123`	`888`	`A`	`1`
`2022-08-07 20:16:38`	`7-974`	`888`	`V`	`1`
`2022-08-09 13:29:43`	`9-390`	`623`	`G`	`1`
`2022-08-10 09:33:57`	`10-862`	`623`	`TT`	`1`
`2022-08-11 16:23:31`	`11-348`	`623`	`XD`	`1`

`Date_`	`transaction_id`	`customer_id`	`product_name`	`qty`
`2022-08-05 10:44:59`	`5-123`	`888`	`A`	`1`
`2022-08-05 10:44:59`	`5-123`	`888`	`A`	`1`
`2022-08-07 20:16:38`	`7-974`	`888`	`V`	`1`
`2022-08-09 13:29:43`	`9-390`	`623`	`G`	`1`
`2022-08-10 09:33:57`	`10-862`	`623`	`TT`	`1`
`2022-08-11 16:23:31`	`11-348`	`623`	`XD`	`1`