参考链接:

http://www.itpub.net/showthread.php?threadid=415889&pagenumber=

alter system switch logfile ;
alter system archive log current ;
alter system archive log all ;

Oracle8i Bible上是这样说的
To have Oracle archive the current
redo log files, issue this command:

ALTER SYSTEM ARCHIVE LOG CURRENT;

This command causes Oracle to switch to a new log file. Oracle then archives all redo log files that have not yet been archived. Another approach to this same task is to issue the following two commands:

ALTER SYSTEM SWITCH LOGFILE;
ALTER SYSTEM ARCHIVE LOG ALL

The first command forces the log switch, and the second causes Oracle to archive all the redo log files that are full but that haven't been archived yet.