MySQL 5.7

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CREATE TABLE TableDate(
month int(20),	
json varchar(500)
)
INSERT TableDate (month,json)
VALUES 
('01','[" 99/01/04", " 99/01/05", " 99/01/06", " 99/01/07"]'),
('02','[" 99/02/04", " 99/02/05", " 99/02/06", " 99/02/07"]'),
('03','[" 99/03/04", " 99/03/05", " 99/03/06", " 99/03/07"]')

Records: 3  Duplicates: 0  Warnings: 0


#原本的Table
select * from TableDate


month
json


1
[" 99/01/04", " 99/01/05", " 99/01/06", " 99/01/07"]

2
[" 99/02/04", " 99/02/05", " 99/02/06", " 99/02/07"]

3
[" 99/03/04", " 99/03/05", " 99/03/06", " 99/03/07"]


CREATE TABLE TableDateHope(
month int(20),	
date varchar(500)
)
INSERT TableDateHope (month,date)
VALUES 
('01','99/01/04'),
('01','99/01/05'),
('01','99/01/06'),
('01','99/01/07'),
('02','99/02/04'),
('02','99/02/05'),
('02','99/02/06'),
('02','99/02/07'),
('03','99/03/04'),
('03','99/03/05'),
('03','99/03/06'),
('03','99/03/07')

Records: 12  Duplicates: 0  Warnings: 0


#理想的Table
select * from TableDateHope


month
date


1
99/01/04

1
99/01/05

1
99/01/06

1
99/01/07

2
99/02/04

2
99/02/05

2
99/02/06

2
99/02/07

3
99/03/04

3
99/03/05

3
99/03/06

3
99/03/07

month	json
1	[" 99/01/04", " 99/01/05", " 99/01/06", " 99/01/07"]
2	[" 99/02/04", " 99/02/05", " 99/02/06", " 99/02/07"]
3	[" 99/03/04", " 99/03/05", " 99/03/06", " 99/03/07"]

month	date
1	99/01/04
1	99/01/05
1	99/01/06
1	99/01/07
2	99/02/04
2	99/02/05
2	99/02/06
2	99/02/07
3	99/03/04
3	99/03/05
3	99/03/06
3	99/03/07