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HomeDatabaseMysql TutorialOracle隐式游标获取记录数

Oracle使用两种光标:显式光标和隐式光标。不管语句返回多少条纪录,PL/SQL为使用的每一条UPDATE、DELETE和INSERT等SQL命令隐式的

怎样统计PLSQL语言中删除语句执行之后一共删除了多少条纪录。

Oracle使用两种光标:显式光标和隐式光标。不管语句返回多少条纪录,PL/SQL为使用的每一条UPDATE、DELETE和INSERT等SQL命令隐式的声明一个光标。(要管理SQL语句的处理,必须隐式的给它定义一个光标。)

在PL/SQL中,,当执行DML语句的时候,会自动打开一个隐式游标(游标就类似JDBC中的ResultSet),而相关要被操作的数据都是会先被放入隐式游标。隐式游标由ORACLE帮我们自动管理,如果想要手动进行一些操作的话,我们可以使用隐式游标的相关属性。如:

SQL%FOUND 成功获取记录返回true,否则返回false

SQL%NOTFOUND 成功获取记录返回true,否则返回false

SQL%ROWCOUNT 返回从游标中获取的记录条数

SQL%ISOPEN 总是返回false

利用隐式游标属性SQL%ROWCOUNT可以达到计算删除了多少条纪录。

可以获取的DML sql包括:INSERT /UPDATE/DELETE /MERGER

具体使用看下面的例子把

create or replace procedure test_02 is
 CNT INT;
begin
  DELETE FROM TEST_01 ;
  cnt:=sql%rowcount;

  commit;
 end; 

create or replace procedure test_03 is
 CNT INT;
 n_1 int;
 n_2 int;
 n_3 int;
begin

 merge into test_04
 using (select * from test_09 )
 merger_subquery
 on(test_04.object_id = merger_subquery.object_id)
 
 when not matched then
 insert (object_id,OBJECT_NAME)
 values (merger_subquery.object_id,merger_subquery.object_name)
 when matched then
 update set object_name = merger_subquery.object_name;
   
  cnt:=sql%rowcount;
  n_1:=cnt;
  
  commit;
 end;

linux

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