Oracle® Database 11g / 12c / 18c error codes ORA-54022: Virtual column expression cannot be changed because an index is defined on column

ORA-54022: Virtual column expression cannot be changed because an index is defined on column

Oracle Error Code: ORA-54022

Cause: Attempted to change the expression of a virtual column that was indexed.

Action: Alter index unsable. Change expression and then rebuild index.