Oracle学习笔记[1] - 自动逻辑备份并删除过期备份

公司上了后台是oracle的应用软件，主任要做自动备份，可惜RMAN还用的不熟，只好是用逻辑备份。要求每天自动备份一次，只保留7天的纪录，过期的备份要自动删除。公司服务器是win2003的操作系统。我写了个脚本用windows的任务计划来执行一共2个文件，一个bat文件用任务计划来执行，一个sql文件执行exp命令，由bat文件调用，在执行备份操作的同时可以写log。

sql文件

rem exp oracle by xiangcns

column today new_val dt

select to_char(sysdate,'YYYY-MM-DD') today from dual;

host echo .>>exp_vprm_loop.log

host echo -&dt->>exp_vprm_loop.log rem 将日期写入log

host echo .[exp_vprm_&dt]>>exp_vprm_loop.log

host echo .exp begin %time:~0,8%.>>exp_vprm_loop.log rem 将时间写入log

host exp userid=admin/admin file=exp_vprm_&dt..dmp log=exp_vprm_&dt..log full=y

host echo .exp end %time:~0,8%.>>exp_vprm_loop.log

exit

bat文件

@rem =========exp oracle============

echo off

set oracle_sid=vprm

sqlplus admin/admin @exp_data.sql

@rem =======set date format=========

@echo off

rem GET YESTERDAY DATE

set dt=%date:~0,10%

set today=%date:~0,10%

rem date format is "YYYY-MM-DD"

rem set /P dt="Input Date: "

set dy=%dt:~0,4%

set dm=%dt:~5,2%

set dd=%dt:~8,2%

@rem ===========show date===========

@rem echo %dt%

@rem ===========condition===========

if %dm%%dd%==0107 goto L01

if %dm%%dd%==0207 goto L02 rem The previous month has 31 day

if %dm%%dd%==0307 goto L07 rem The previous month is February

if %dm%%dd%==0407 goto L02

if %dm%%dd%==0507 goto L04 rem The previous month has 30 day

if %dm%%dd%==0607 goto L02

if %dm%%dd%==0707 goto L04

if %dm%%dd%==0807 goto L02

if %dm%%dd%==0907 goto L02

if %dm%%dd%==1007 goto L05

if %dm%%dd%==1107 goto L03

if %dm%%dd%==1207 goto L06

if %dd%==08 goto L10

if %dd%==09 goto L10

if %dd%==10 goto L12

if %dd%==11 goto L12

if %dd%==12 goto L12

if %dd%==13 goto L12

if %dd%==14 goto L12

if %dd%==15 goto L12

if %dd%==16 goto L11

set /A dd=dd-7 rem subtract 7

set dt=%dy%-%dm%-%dd%

goto CHECK

@rem ============day================

:L10

set /A dd=%dd:~1,1%-7 rem subtract 7

set dt=%dy%-%dm%-0%dd%

goto CHECK

:L11

set dt=%dy%-%dm%-09

goto CHECK

:L12

rem set /A dd=%dd:~0,1%-7 rem subtract 7

set /A dd=%dd%-7 rem subtract 7

set dt=%dy%-%dm%-0%dd%

goto CHECK

@rem =============month==============

:L02

set /A dm=%dm:~1,1%-1

set dt=%dy%-0%dm%-31

goto CHECK

:L04

set /A dm=dm-1

set dt=%dy%-0%dm%-30

goto CHECK

@rem =============month==============

:L05

set dt=%dy%-09-30

goto CHECK

:L03

set dt=%dy%-10-31

goto CHECK

:L06

set dt=%dy%-11-30

goto CHECK

:L01

set /A dy=dy-1

set dt=%dy%-12-31

goto CHECK

@rem============run month=============

:L07

set /A "dd=dy%%4"

if not %dd%==0 goto L08

set /A "dd=dy%%100"

if not %dd%==0 goto L09

set /A "dd=dy%%400"

if %dd%==0 goto L09

:L08

set dt=%dy%-02-28

goto CHECK

:L09

set dt=%dy%-02-29

goto CHECK

@rem=============check=================

:CHECK

if not exist exp_vprm_%today%.dmp goto E01

echo .dmp create successed.>>exp_vprm_loop.log

goto C01

:C01

if not exist exp_vprm_%today%.log goto E02

echo .log create successed.>>exp_vprm_loop.log

goto EXECUTE

:E01

echo .error:dmp do not create successful.>>exp_vprm_loop.log

goto C01

:E02

echo .error:log do not create successful.>>exp_vprm_loop.log

goto EXECUTE

@rem==========del overdue==============

:EXECUTE

@rem echo %dt%

if not exist exp_vprm_%dt%.dmp goto EXE01

del D:/vprm_bk/exp_vprm_%dt%.dmp

echo .exp_vprm_%dt%.dmp has been deleted at %today% %time:~0,8%.>>D:/vprm_bk/exp_vprm_loop.log

goto EXE02

:EXE01

echo .can not find exp_vprm_%dt%.dmp，deletion is break off at %today% %time:~0,8%.>>D:/vprm_bk/exp_vprm_loop.log

goto EXE02

:EXE02

if not exist exp_vprm_%dt%.log goto EXE03

del D:/vprm_bk/exp_vprm_%dt%.log

echo .exp_vprm_%dt%.log has been deleted at %today% %time:~0,8%.>>D:/vprm_bk/exp_vprm_loop.log

goto END

:EXE03

echo .can not find exp_vprm_%dt%.log，deletion is break off at %today% %time:~0,8%.>>D:/vprm_bk/exp_vprm_loop.log

goto END

@rem==============end==================

:END

echo .all execute finished at %today% %time:~0,8%.>>D:/vprm_bk/exp_vprm_loop.log

bat文件的主要操作是

（1）连接到数据库

（2）计算今天的日期和7天前的日期，其实代码这么长主要的篇幅就是算日期和写log日志，log有一个好处，可以检查有没有错误的删除记录，包括哪天创建备份文件成功或者失败，代码的check段和del段主要就是检查并记录log。计算日期是因为备份文件就是以项目名加日期的方式进行的。

（3）调用sql文件执行exp

这样的备份方式对于业务主要集中在8小时的工作时间而不是24小时运转的中小企业是完全够用了，而且恢复也很方便，drop掉、create再imp就OK了，这个代码其实性能还是很简单的，虽说实现了全部期望的功能，但是不得不承认，写成这样其实还是很土鳖的，哈哈。