在PL/SQL中如何让程序暂停几秒钟

 

在编写PL/SQL中，有时需要程序中暂停几秒钟再继续执行，查了一下，oracle内置有这个功能dbms_lock.sleep(10)；不过dbms_lock包需要用户自己安装，演示如下：

 

C:\Documents and Settings\andyleng>sqlplus /nolog

SQL*Plus: Release 11.2.0.1.0 Production on Thu Nov 10 10:04:56 2011

Copyright (c) 1982, 2010, Oracle.  All rights reserved.

SQL> conn /as sysdba　　--以SYSDBA身份登陆
Connected.
SQL> @?/rdbms/admin/dbmslock.sql　--安装系统包

Package created.


Synonym created.


Grant succeeded.

SQL> grant execute on dbms_lock to public;　--授权PUBLIC执行权限

Grant succeeded.

SQL> create table test1(id number,name varchar2(40),time date);   --创建test1临时表

Table created.

SQL> select * from test1;  --无数据

no rows selected


SQL> SET TIMING ON  --打开时间显示
SQL> begin  --开始执行测试脚本
  2    insert into test1(id,name,time) values(1,'Andy',sysdate);
  3    DBMS_LOCK.SLEEP(10);  --让程序暂时10秒钟
  4    insert into test1(id,name,time) values(2,'Shirley',sysdate);
  5    commit;
  6  end;
  7  /

PL/SQL procedure successfully completed.

Elapsed: 00:00:10.04  --程序执行时间为10.04秒


SQL> SELECT ID,NAME,TO_CHAR(TIME,'YYYY/MM/DD HH24:MI:SS') AS TIME FROM TEST1;　--查询执行结果

        ID NAME                                     TIME
---------- ---------------------------------------- -------------------
         1 Andy                                     2011/11/10 10:09:03   --第一条的插入时间是09:03
         2 Shirley                                  2011/11/10 10:10:13   --第二条的插入时间是09:13,刚好比第一条晚了10秒钟


Elapsed: 00:00:00.00


SQL> drop table test1;

Table dropped.

 

 自定义EXCEPTION 和GOTO的用法：

-- Create the procedure to loop del users.
CREATE OR REPLACE PROCEDURE QA2_ATGCORE_MF.delBigTab
AS
       PRAGMA AUTONOMOUS_TRANSACTION;
       p_Count   NUMBER := 1000;
       n_delete number:=0;
       start_time date:=sysdate;
       end_time date;
       var_usergroup number;
	   e_nowait EXCEPTION;--自定义exception
	   PRAGMA EXCEPTION_INIT(e_nowait,-00054);--初使化该exception到“ORA-00054”的错误代码
BEGIN
   <<restart>>--程序标签
   WHILE 1 = 1
   LOOP
           begin
                  var_usergroup:=QA2_ATGCORE_MF.DEL_USERGROUP_SEQ.nextval;
				  EXECUTE IMMEDIATE
                     'update QA2_ATGCORE_MF.DPS_USER_DEL_TEMP set usergroup_id=:usergroup,del_flag=''1'',del_time=sysdate where del_flag=''0'' and rownum <=:rn'
                     USING var_usergroup,P_COUNT;
                  IF (SQL%NOTFOUND)
                     OR (TO_CHAR (SYSDATE, 'hh24mi') BETWEEN '0600' AND '1200')
                  THEN
                     EXIT;
                  ELSE
                     n_delete:=n_delete + SQL%ROWCOUNT;
					 QA2_ATGCORE_MF.DEL_USERGROUP(var_usergroup);
                  END IF;
                  COMMIT;           
		   EXCEPTION
                WHEN e_nowait THEN
                   DBMS_LOCK.SLEEP(2););--出现ORA-00054的错误时先等待2秒钟
				   DBMS_OUTPUT.PUT_LINE(TO_CHAR(SYSDATE,'YYYY/MM/DD HH24:MI:SS')||SQLCODE||':'||SQLERRM||' I am go to restart' );
                   GOTO restart;--出现ORA-00054的错误时跳转到restart处重新执行该程序
               WHEN OTHERS THEN
                   ROLLBACK;
                   RAISE;
		   END;
		   
   END LOOP;
   COMMIT;
   end_time:=sysdate;
   DBMS_OUTPUT.PUT_LINE('***************************************************************************');
   DBMS_OUTPUT.PUT_LINE('Totally delete '||to_char(n_delete)||' users! Used time:'||numtodsinterval (end_time-start_time,'DAY'));
   DBMS_OUTPUT.PUT_LINE('***************************************************************************');
END;
/