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create table tbl (t1 int, t2 varchar(10), t3 varchar(10));
insert into tbl (t1, t2, t3) values
(1, '01', 'M6'),
(1, '02', 'M6'),
(2, '01', 'M1'),
(2, '01', 'M1'),
(2, '02', 'M1'),
(3, '04', 'M4'),
(3, '04', 'M4'),
(4, '01', 'M1'),
(4, '01', 'M2');
9 rows affected
with cte as (
select
t1, t2, t3,
ROW_NUMBER() OVER (PARTITION BY t1, t2, t3 order by t1, t2, t3) rn from tbl
)
delete from cte
where rn > 1;
2 rows affected
select * from tbl
| t1 | t2 | t3 |
|---|---|---|
| 1 | 01 | M6 |
| 1 | 02 | M6 |
| 2 | 01 | M1 |
| 2 | 02 | M1 |
| 3 | 04 | M4 |
| 4 | 01 | M1 |
| 4 | 01 | M2 |