ORA-28100: policy function schema string is invalid
Cause: The schema was dropped after the policy associated with the function had been added to the object.
Action: Drop the policy and re-create it with a policy function owned by a valid user. Or re-create the user and the policy function under the new user.
ORA-28100错误是由于客户端操作失误导致的。
ORA-28100: policy function schema string is invalid
Cause: The user attempted to execute a policy function while connected to a schema which is not authorized to perform the operation. This is usually due to an attempt to use a policy function in a non-native environment.
Action: Ensure that the policy function being queried is in the correct schema and that the user has the necessary privilege to execute the policy function.
最常见的ORA-28100错误案例是在用户尝试使用授权的函数的时候，确实存在函数但是因为某些原因没有权限执行该函数。
1.检查函数是否存在。
2.检查用户是否有权限执行该函数。
3.检查该函数是否在正确的模式中。
4.尝试重新设置函数的权限（如果有必要）。