ORA-30015: previously offlined undo tablespace

admin

ORA-30015: previously offlined undo tablespace 'string' is still pending
Cause: the current operationis not allowed because an undo tablespace
containing active transactions is pending from a previous SWITCH UNDO
operation. The operation will be allowed again after all transactions in the
previous undo tablespace are committed.
Action: Wait for all previoustransactions to commit before reissuing the current
statement.