Copy all data files, control files and online redo logs file to backup media.

将所有数据文件、控制文件和联机重做日志文件复制到备份媒介。

youdao

Creates the online redo log files if they do not currently exist.

联机日志损坏，不能做完整修复时，用的。

youdao

Creates the online redo log files if they do not currently exist.

联机日志损坏，不能做完整修复时，用的。

youdao