在正常使用ORACLE的过程中，作为数据的主要存储者，我们要对数据负责，因为数据是一个系统最核心的东西，没有了数据一切都失去了具体的意义，所以我们要做备份计划，保证在不可抗外力下数据的可恢复性，所以我们需要做定时计划，但是linux下任务计划不像windows，很多东西需要自己来配置，具体配置如下：

#!/bin/ksh
# Oracle Environment settings
PATH=/usr/bin:/usr/ucb:/etc:.:/usr/X/bin:/bin
export PATH
ORACLE_SID=orcl1; export ORACLE_SID
ORACLE_BASE=/u01/app/oracle; export ORACLE_BASE
ORACLE_HOME=$ORACLE_BASE/product/11.2.0/dbhome_1;  export ORACLE_HOME
ORA_NLS33=$ORACLE_HOME/ocommon/nls/admin/data ; export ORA_NLS33
TNS_ADMIN=$ORACLE_HOME/network/admin ; export TNS_ADMIN
LD_LIBRARY_PATH=$ORACLE_HOME/lib ; export LD_LIBRARY_PATH
PATH=$ORACLE_HOME/bin:/usr/local/bin:/usr/ccs/bin:$PATH:/usr/sbin
export PATH
CLASSPATH=$ORACLE_HOME/jlib:$ORACLE_HOME/product/jlib ; export CLASSPATH
backup_dir=/backup
datetime=`date +"%Y-%m-%d"`
# options
# export NLS_LANG=AMERICAN_AMERICA.ZHS16GBK
# export DATA_DIR=/home/bak/data
# export LOGS_DIR=/home/bak/log
# export BAKUPTIME=date +%Y%m%d%H%M%S
# 
DMP_FILE=Data_bak.dmp
LOG_FILE=Log_bak.log
#
#  Let's start with an export of the database
#
expdp expdp/expdp DIRECTORY=dump_dir SCHEMAS=schema_name  DUMPFILE=$DMP_FILE logfile=$LOG_FILE statistics=none; 
#
# Just to be safe (with space),we'll compress the export file
#
if [ -e $backup_dir/$DMP_FILE ]; then
cd /backup
rar a -df DBZY_JTGL.rar $DMP_FILE

else 
	echo "no dmp file"
	exit
fi
#
# Let's delete the backups and logs that are more than 1 days old
find $backup_dir -name "*" -mtime +10 -exec rm {} /;
# end