Oracle Error Message
ORA-30553: The function is not deterministic
Reason for the Error
The function on which the index is defined is not deterministic
Solution
If the function is deterministic, mark it DETERMINISTIC. If it is not deterministic (it depends on package state, database state, current time, or anything other than the function inputs) then do not create the index. The values returned by a deterministic function should not change even when the function is rewritten or recompiled.