MySQL 8.0

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CREATE TABLE tmpnav(Odnumber varchar(20), UAccount varchar(20));
insert into tmpnav values ('2018101610001','d10516137');
insert into tmpnav values ('2018101610001','d10516137');
insert into tmpnav values ('2018101610001','d10516137');
insert into tmpnav values ('2018102000005','d10516127');
insert into tmpnav values ('2018103100020','d10516101');
insert into tmpnav values ('2019030100001','d10516101');
select *
from tmpnav;


Odnumber
UAccount


2018101610001
d10516137

2018101610001
d10516137

2018101610001
d10516137

2018102000005
d10516127

2018103100020
d10516101

2019030100001
d10516101


SELECT 	
DENSE_RANK() OVER (ORDER BY Odnumber ASC) AS ItemNo,
Odnumber,UAccount
FROM tmpnav
ORDER BY Odnumber ASC


ItemNo
Odnumber
UAccount


1
2018101610001
d10516137

1
2018101610001
d10516137

1
2018101610001
d10516137

2
2018102000005
d10516127

3
2018103100020
d10516101

4
2019030100001
d10516101

Odnumber	UAccount
2018101610001	d10516137
2018101610001	d10516137
2018101610001	d10516137
2018102000005	d10516127
2018103100020	d10516101
2019030100001	d10516101