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WITH t(id,col) AS
(
SELECT 1,'1234567' FROM dual UNION ALL
SELECT 2,'12345678' FROM dual
)
SELECT id,LISTAGG( SUBSTR(col,1+(level-1)*2,2)||
CASE WHEN level < CEIL(LENGTH(col)/2)
THEN
CHR(TRUNC(DBMS_RANDOM.VALUE(33,48)))
END)
WITHIN GROUP (ORDER BY level)
AS result
FROM t
GROUP BY id
CONNECT BY level <= CEIL(LENGTH(col)/2)
AND PRIOR SYS_GUID() IS NOT NULL
AND PRIOR ID = ID
| ID | RESULT |
|---|---|
| 1 | 12*34&56.7 |
| 2 | 12#34!56-78 |