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CREATE TABLE tab
AS
SELECT 1 AS col1 , 1 AS col2 , 2 AS col3
UNION ALL SELECT 1 , 1, 2
UNION ALL SELECT 1, 2 , 2
SELECT *,CONCAT('newid', DENSE_RANK() OVER(ORDER BY col1,col2,col3)) AS newcol
FROM tab
| col1 | col2 | col3 | newcol |
|---|---|---|---|
| 1 | 1 | 2 | newid1 |
| 1 | 1 | 2 | newid1 |
| 1 | 2 | 2 | newid2 |