ORA-01621: cannot rename member of current log if database is open
Cause: This is a rename command for a member of the current log for an open thread. If the database is open anywhere, the log may be in use, so the rename cannot be done.
Action: Wait until the log is not current, or mount the database exclusively.
ORA-01621错误发生时，用户在改变一个特定的redo日志文件的名字，当然数据库实例必须要处于打开状态这个错误。
ORA-01621: cannot rename member of current log of open database
Cause: An attempt to change the name of the currently used redo thread member of an open database was made.
Action: Wait until the current log is archived before renaming the member.
一个用户尝试在数据库打开的情况下更改当前使用的redo线程成员的名称。
1.关闭数据库；
2.重命名redo日志文件；
3.开启数据库实例。