用存储过程实现删除数据表的部分记录

在实际的工作和学习中，许多人经常需要分别删除数据表的某些记录，分批提交以此来减少对于Undo的使用，下面我们提供一个简单的存储过程来实现此逻辑。

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 ** Condition with default value "1=1" and default Commit batch is 10000. 7 **/ 8 ( 9 p_TableName in varchar2, -- The TableName which you want to delete from 10 p_Condition in varchar2 default "1=1", -- Delete condition, such as "id>=100000" 11 p_Count in varchar2 default "10000" -- 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.

注释：在此实例中修正了一下,增加了2个缺省值,以下是具体过程:

create or replace procedure deleteTab
(                                                                                               
  p_TableName    in    varchar2,   
-- The TableName which you want to delete from              
  p_Condition    in    varchar2 default "1=1",  
 -- Delete condition, such as "id>=100000"                   
  p_Count        in    varchar2 default "10000"   
-- Commit after delete How many records                     
)                                                                                               
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!");

注释：读者可以根据自己的实际情况来进行适当的调整