ORA-28231: no data passed to obfuscation toolkit
Cause: A NULL value was passed to a function or procedure.
Action: Make sure that the data passed is not empty.
ORA-28231：是由于使用 Oracle 数据库的Obfuscation Toolkit（OTK）时出现的错误，表明没有传递数据给OTK。
ORA-28231: no data passed to obfuscation toolkit
Cause: An attempt was made to obfuscate data with the Oracle Database Obfuscation Toolkit (OTK), but no data was passed to the toolkit.
Action: Pass data to the Oracle Database Obfuscation Toolkit, and retry the operation.
当在OTK的函数中没有传递数据给OTK时，就会出现ORA-28231错误。
1、确认自己的程序是否正确的传递了数据给OTK。
2、如果数据没有传递，需要修改程序，将数据传递给OTK。
3、重新尝试操作。