ORA-16516: current state is invalid for the attempted operation
Cause: The broker may have returned this error for either switchover operations or for database state change operations. If this error was returned for a switchover operation, the broker determined that either:
– The databases changing roles are shut down.
– The primary database is not shipping redo data.
– The standby database that will become the primary database is not applying redo data. If this error was returned for database state change operations, the database state specified was invalid.
Action: If this error is returned when attempting a switchover operation, make sure that:
– The databases changing roles are started.
– The primary database is shipping redo data.
– The standby database is applying redo data. If this error is returned when attempting a database state change operation, make sure a valid database state is specified.
ORA-16516：当前状态对于所尝试操作无效
ORA-16516表示当前在操作数据库实例时，当前的状态与所尝试的操作不匹配。
当工作者进程（oracle worker process）被禁用时，尝试执行涉及工作者进程改变状态或操作时可能会出现ORA-16516错误。
1.首先要检查数据库实例的状态，是否允许尝试的操作。
2.可用v$process视图检查进程是否处于正确的状态。如果不正确，可使用alter session命令重新创建工作者进程以更改状态
3.如果以上处理无效，可能需要在实例中执行shutdown重新启动进程或等待3层确认后重新启动实例。