如何有条件的分步删除数据表中的记录

如何有条件的分步删除数据表中的记录

作者:eygle

出处:http://blog.eygle.com

日期:February 22, 2005

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有时候我们需要分配删除数据表的一些记录，分批提交以减少对于Undo的使用，本文提供一个简单的存储过程用于实现该逻辑。
你可以根据你的需要进行适当调整，本例仅供参考:

SQL> create table test as select * from dba_objects;

Table created.

SQL> create or replace procedure deleteTab
  2  /**
  3   ** Usage: run the script to create the proc deleteTab
  4   **        in SQL*PLUS, type "exec deleteTab('Foo','ID>=1000000','3000');"
  5   **        to delete the records in the table "Foo", commit per 3000 records.
  6   **      
  7   **/
  8  (
  9    p_TableName    in    varchar2,    -- The TableName which you want to delete from
 10    p_Condition    in    varchar2,    -- Delete condition, such as "id>=100000"
 11    p_Count        in    varchar2     -- Commit after delete How many records
 12  )
 13  as
 14   pragma autonomous_transaction;
 15   n_delete number:=0;
 16  begin
 17   while 1=1 loop
 18     EXECUTE IMMEDIATE
 19       'delete from '||p_TableName||' where '||p_Condition||' and rownum <= :rn'
 20     USING p_Count;
 21     if SQL%NOTFOUND then
 22     exit;
 23     else
 24          n_delete:=n_delete + SQL%ROWCOUNT;
 25     end if;
 26     commit;
 27   end loop;
 28   commit;
 29   DBMS_OUTPUT.PUT_LINE('Finished!'); 
 30   DBMS_OUTPUT.PUT_LINE('Totally '||to_char(n_delete)||' records deleted!');
 31  end;
 32  /

Procedure created.


SQL> insert into test select * from dba_objects;

6374 rows created.

SQL> /

6374 rows created.

SQL> /

6374 rows created.

SQL> commit;

Commit complete.

SQL> exec deleteTab('TEST','object_id >0','3000')
Finished!
Totally 19107 records deleted!

PL/SQL procedure successfully completed.

很简单，但是想来也有人可以用到。