SQL Server 2019

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create table DateDim (name varchar(50), somedata int)

insert into DateDim values ('1', 1), ('2', 2), ('2', 3), ('1', 5)

select * from DateDim


name
somedata


1
1

2
2

2
3

1
5


alter table DateDim add DateID int not null identity (109574, 1)
alter table DateDim add constraint PK_DateDim_ID primary key (DateID)

select * from DateDim


name
somedata
DateID


1
1
109574

2
2
109575

2
3
109576

1
5
109577


drop table DateDim