Sikker TO_NUMBER()

Fra Oracle Database 12c Release 2 du kan bruge TO_NUMBER med DEFAULT ... ON CONVERSION ERROR :

SELECT TO_NUMBER('*' DEFAULT 0 ON CONVERSION ERROR) AS "Value"
FROM DUAL;

Eller CAST :

SELECT CAST('*' AS NUMBER DEFAULT 0 ON CONVERSION ERROR) AS "Value"
FROM DUAL;

db<>fiddle-demo