Oracle Solution for Error ora-40281

Solution for Oracle Error ORA-40281

ORA-40281: invalid model name

What triggered the Error:

A model name is invalid or does not exist.

What should we do to fix it:

Check spelling. A valid model name must begin with a letter and may contain only alphanumeric characters and the special characters $, _, and #. The name must be less than or equal to 30 characters and cannot be a reserved word.