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SELECT
LISTAGG(X, ',') WITHIN GROUP(
ORDER BY
X
) as result
FROM
(
SELECT
X,
SUM(LENGTH(X)) OVER(
ORDER BY
X
) LENGTH_X,
COUNT(1) OVER(
ORDER BY
X
) - 1 AS COMMAS
FROM
(
SELECT
LEVEL X
FROM
DUAL
CONNECT BY
LEVEL <= 20
)
)
GROUP BY
CEIL((LENGTH_X + COMMAS) / 15)
| RESULT |
|---|
| 1,2,3,4,5,6,7,8 |
| 9,10,11,12,13 |
| 14,15,16,17,18 |
| 19,20 |