将ALERT LOG当成一个外部表进行访问，可以更方便的读取ALERT LOG。

首先查到DUMP的目录：
SELECT * FROM v$parameter WHERE NAME LIKE '%dump%';
对DUMP的目录建立一个DIRECTORY：
CREATE DIRECTORY DIR_DUMP AS '/home/oracle/oracle/product/10.2.0/admin/beta01/bdump';
将ALERT LOG定义成一个外部表：
create table alert_log
( text varchar2(4000))
 organization external(
 type oracle_loader
 default directory DIR_DUMP
 access parameters(
  records delimited by newline
  nobadfile
  nodiscardfile
  nologfile)
 location('alert_beta01.log')
)reject limit UNLIMITED;
查询ALERT_LOG表就可以直接读到ALERT LOG的日志。
select * from alert_log where rownum < 20;

Mon Oct 10 09:17:57 2011
Starting ORACLE instance (normal)
LICENSE_MAX_SESSION = 0
LICENSE_SESSIONS_WARNING = 0
Shared memory segment for instance monitoring created
Picked latch-free SCN scheme 1
Using LOG_ARCHIVE_DEST_10 parameter default value as USE_DB_RECOVERY_FILE_DEST
Autotune of undo retention is turned on.
IMODE=BR
ILAT =18
LICENSE_MAX_USERS = 0
SYS auditing is disabled
ksdpec: called for event 13740 prior to event group initialization
Starting up ORACLE RDBMS Version: 10.2.0.1.0.
System parameters with non-default values:
  processes                = 150
  nls_language             = SIMPLIFIED CHINESE
  nls_territory            = CHINA
  sga_target               = 1845493760