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WITH data AS (
SELECT 255 AS col FROM DUAL
UNION ALL
SELECT 25555 FROM DUAL
UNION ALL
SELECT 2444 FROM DUAL
UNION ALL
SELECT 2555.5 FROM DUAL
)
SELECT col, ROUND(col / POWER(10,TRUNC(LOG(10, col)))) * POWER(10,TRUNC(LOG(10,col)))
FROM Data
| COL | ROUND(COL/POWER(10,TRUNC(LOG(10,COL))))*POWER(10,TRUNC(LOG(10,COL))) |
|---|---|
| 255 | 300 |
| 25555 | 30000 |
| 2444 | 2000 |
| 2555.5 | 3000 |