MySQL 5.7

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CREATE TABLE TableDate(
month int(20),	
json varchar(500)
)
INSERT TableDate (month,json)
VALUES 
('01','[" 99/01/02", " 99/01/05", " 99/01/06", " 99/01/07"," 99/01/08"," 99/01/09"]'),
('02','[" 99/02/04", " 99/02/05", " 99/02/08", " 99/02/09"]'),
('03','[" 99/03/01", " 99/03/02", " 99/03/03", " 99/03/06", " 99/03/07", " 99/03/08", " 99/03/09", " 99/03/10"]')

Records: 3  Duplicates: 0  Warnings: 0


#原本的Table
select * from TableDate


month
json


1
[" 99/01/02", " 99/01/05", " 99/01/06", " 99/01/07"," 99/01/08"," 99/01/09"]

2
[" 99/02/04", " 99/02/05", " 99/02/08", " 99/02/09"]

3
[" 99/03/01", " 99/03/02", " 99/03/03", " 99/03/06", " 99/03/07", " 99/03/08", " 99/03/09", " 99/03/10"]


CREATE TABLE TableDateHope(
month int(20),	
date varchar(500)
)
INSERT TableDateHope (month,date)
VALUES 
('01','99/01/02'),
('01','99/01/05'),
('01','99/01/06'),
('01','99/01/07'),
('01','99/01/08'),
('01','99/01/09'),
('02','99/02/04'),
('02','99/02/05'),
('02','99/02/08'),
('02','99/02/09'),
('03','99/03/01'),
('03','99/03/02'),
('03','99/03/03'),
('03','99/03/06'),
('03','99/03/07'),
('03','99/03/08'),
('03','99/03/09'),
('03','99/03/10')

Records: 18  Duplicates: 0  Warnings: 0


#理想的Table
select * from TableDateHope


month
date


1
99/01/02

1
99/01/05

1
99/01/06

1
99/01/07

1
99/01/08

1
99/01/09

2
99/02/04

2
99/02/05

2
99/02/08

2
99/02/09

3
99/03/01

3
99/03/02

3
99/03/03

3
99/03/06

3
99/03/07

3
99/03/08

3
99/03/09

3
99/03/10

month	json
1	[" 99/01/02", " 99/01/05", " 99/01/06", " 99/01/07"," 99/01/08"," 99/01/09"]
2	[" 99/02/04", " 99/02/05", " 99/02/08", " 99/02/09"]
3	[" 99/03/01", " 99/03/02", " 99/03/03", " 99/03/06", " 99/03/07", " 99/03/08", " 99/03/09", " 99/03/10"]

month	date
1	99/01/02
1	99/01/05
1	99/01/06
1	99/01/07
1	99/01/08
1	99/01/09
2	99/02/04
2	99/02/05
2	99/02/08
2	99/02/09
3	99/03/01
3	99/03/02
3	99/03/03
3	99/03/06
3	99/03/07
3	99/03/08
3	99/03/09
3	99/03/10