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WITH data AS (
SELECT 121 AS col FROM DUAL
UNION ALL
SELECT 255 AS col FROM DUAL
UNION ALL
SELECT 744 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, -TRUNC(LOG(10, col))) AS rounded,
ROUND(4 * col, -TRUNC(LOG(10, col))) / 4 AS quarters
FROM Data
| COL | ROUNDED | QUARTERS |
|---|---|---|
| 121 | 100 | 125 |
| 255 | 300 | 250 |
| 744 | 700 | 750 |
| 25555 | 30000 | 25000 |
| 2444 | 2000 | 2500 |
| 2555.5 | 3000 | 2500 |