ORA-00911: invalid character

ORA-00911: invalid character
Cause: identifiers may not start with any ASCII character other than letters and  numbers. $#_ are
also allowed after the first character. Identifiers enclosed by  doublequotes may contain any character other than a doublequote. Alternative  quotes (q"#...#") cannot use spaces, tabs, or carriage returns as delimiters. For all  other contexts, consult the SQL Language Reference Manual.
Action: none