loading
alter system switch logfile;
目标库：
tail –f /app/oracle/diag/rdbms/oem_dg/oem/trace/ alert_oem.log
二十一、
检查日志传输：
SELECT a.th, a.seq transfered, b.seq archived
FROM (SELECT local.thread# th, MAX (local.sequence#) seq FROM (SELECT thread#, sequence# FROM v$archived_log WHERE dest_id = 1) local WHERE local.sequence# IN (SELECT sequence# FROM v$archived_log
WHERE dest_id = 2 AND thread# = local.thread#) GROUP BY local.thread#) a,
(SELECT thread# th, MAX (sequence#) seq FROM v$archived_log WHERE dest_id = 1 GROUP BY thread#) b WHERE a.th = b.th ORDER BY 1;