SQL Server 2017

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create table Organization (
    organizationId int identity(1, 1) primary key, 
    provinceId int, 
    CityId int, 
    TownId int 
);
Insert Into Organization (provinceId, CityId, TownId) 
    select provinceId, CityId, TownId
    from (values ('1,2,3'), ('3,2,1'), ('4,5,3')) v(str) cross apply
         (select max(case when seqnum = 1 then p.value end) as provinceid,
                 max(case when seqnum = 2 then p.value end) as cityid,
                 max(case when seqnum = 3 then p.value end) as townid                 
          from (select p.*,
                       row_number() over (order by charindex(',' + p.value + ',', ',' + v.str + ',')) as seqnum
                from string_split(v.str, ',') p
               ) p
         ) s;
Warning: Null value is eliminated by an aggregate or other SET operation.
3 rows affected

select *
from organization


organizationId
provinceId
CityId
TownId


1
1
2
3

2
3
2
1

3
4
5
3