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create table tbl
(
Id int identity(1,1)
, Prod varchar(1)
, Id2 int
)
insert into tbl values ('A', 11), ('A', 11), ('A', 11), ('B', 12), ('B', 12), ('A', 13), ('B', 14), ('D', 15)
8 rows affected
select *
, case
when row_number() over (partition by Id2 order by Id) = 1 then 0
else 1
end Flag
from tbl
order by Id
| Id | Prod | Id2 | Flag |
|---|---|---|---|
| 1 | A | 11 | 0 |
| 2 | A | 11 | 1 |
| 3 | A | 11 | 1 |
| 4 | B | 12 | 0 |
| 5 | B | 12 | 1 |
| 6 | A | 13 | 0 |
| 7 | B | 14 | 0 |
| 8 | D | 15 | 0 |