Oracle中大批量删除数据的方法

批量删除海量数据通常都是很复杂及缓慢的,方法也很多,但是通常的概念是:分批删除,逐次提交。
下面是我的删除过程,我的数据表可以通过主键删除,测试过Delete和For all两种方法,for all在这里并没有带来性能提高,所以仍然选择了批量直接删除。

首先创建一下过程,使用自制事务进行处理:

create or replace procedure delBigTab
(
p_TableName       in    varchar2,
p_Condition       in    varchar2,
p_Count        in    varchar2
)
as
pragma autonomous_transaction;
n_delete number:=0;
begin
while 1=1 loop
EXECUTE IMMEDIATE
'delete from '||p_TableName||' where '||p_Condition||' and rownum <= :rn'
USING p_Count;
if SQL%NOTFOUND then
exit;
else
n_delete:=n_delete + SQL%ROWCOUNT;
end if;
commit;
end loop;
commit;
DBMS_OUTPUT.PUT_LINE('Finished!');
DBMS_OUTPUT.PUT_LINE('Totally '||to_char(n_delete)||' records deleted!');
end;

以下是删除过程及时间:
SQL> create or replace procedure delBigTab
  (
    p_TableName       in    varchar2,
    p_Condition       in    varchar2,
    p_Count        in    varchar2
  )
  as
   pragma autonomous_transaction;
   n_delete number:=0;
 10  begin
 11   while 1=1 loop
 12     EXECUTE IMMEDIATE
 13       'delete from '||p_TableName||' where '||p_Condition||' and rownum <= :rn'
 14     USING p_Count;
 15     if SQL%NOTFOUND then
 16        exit;
 17     else
 18              n_delete:=n_delete + SQL%ROWCOUNT;
 19     end if;
 20     commit;
 21   end loop;
 22   commit;
 23   DBMS_OUTPUT.PUT_LINE('Finished!');
 24   DBMS_OUTPUT.PUT_LINE('Totally '||to_char(n_delete)||' records deleted!');
 25  end;
 26  /

Procedure created.

SQL> set timing on
SQL> select min(NUMDLFLOGGUID) from HS_DLF_DOWNLOG_HISTORY;

MIN(NUMDLFLOGGUID)
------------------
          11000000

Elapsed: 00:00:00.23
SQL> exec delBigTab('HS_DLF_DOWNLOG_HISTORY','NUMDLFLOGGUID < 11100000','10000');

PL/SQL procedure successfully completed.

Elapsed: 00:00:18.54
SQL> select min(NUMDLFLOGGUID) from HS_DLF_DOWNLOG_HISTORY;

MIN(NUMDLFLOGGUID)
------------------
          11100000

Elapsed: 00:00:00.18
SQL> set serveroutput on
SQL> exec delBigTab('HS_DLF_DOWNLOG_HISTORY','NUMDLFLOGGUID < 11200000','10000');
Finished!
Totally 96936 records deleted!

PL/SQL procedure successfully completed.

Elapsed: 00:00:18.61
10万记录大约19s

SQL> exec delBigTab('HS_DLF_DOWNLOG_HISTORY','NUMDLFLOGGUID < 11300000','10000');
Finished!
Totally 100000 records deleted!

PL/SQL procedure successfully completed.

Elapsed: 00:00:18.62
SQL> exec delBigTab('HS_DLF_DOWNLOG_HISTORY','NUMDLFLOGGUID < 11400000','10000');
Finished!
Totally 100000 records deleted!

PL/SQL procedure successfully completed.

Elapsed: 00:00:18.85
SQL>
SQL> exec delBigTab('HS_DLF_DOWNLOG_HISTORY','NUMDLFLOGGUID < 13000000','10000');
Finished!
Totally 1000000 records deleted!

PL/SQL procedure successfully completed.

Elapsed: 00:03:13.87

100万记录大约3分钟
SQL> exec delBigTab('HS_DLF_DOWNLOG_HISTORY','NUMDLFLOGGUID < 20000000','10000');
 
Finished!
Totally 6999977 records deleted!

PL/SQL procedure successfully completed.

Elapsed: 00:27:24.69
700万大约27分钟

posted @ 2015-01-30 15:25  刘竹青  阅读(2666)  评论(1编辑  收藏  举报