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mysql 存储过程事例

Jun 07, 2016 pm 04:27 PM
mysqlexamplestorageprocess

mysql 存储过程例子 (1)循环遍历值 drop procedure if exists doit ;/* *delimiter表示以//结束编译 * */delimiter //create procedure doit (in parameter integer)begindeclare v1 int ;set v1 = parameter ;set parameter = 90 ;while v10 doselect now(

mysql 存储过程例子
(1)循环遍历值

drop procedure if exists doit ;
/*
 *delimiter表示以//结束编译
 *
 */
delimiter //

create procedure doit (in parameter integer)
begin
declare v1 int ;
set v1 = parameter ;
set parameter = 90 ;
while v1>0 do
	select now();
	set v1 = v1 - 1 ;
end while ;

select parameter ;
end;
//
delimiter ;


(2)动态执行sql并注入参数

drop procedure if exists test_insert ;
-- delimiter表示以//结束编译
delimiter //

create procedure test_insert(in num int)  
  begin
     -- 使用变量时不能使用declare 只能用set @id = .. 模式
     -- declare v1 int(11);
     set @v1=num ;
     -- declare sql varchar(200);
     -- declare name varchar(20);
     set @name='wxlan' ;
     set @sql='insert into test values(?,?,now())' ;
     prepare state_ from @sql ;
     while @v1 > 0  do
		execute state_ using @v1,@name ;
		set @v1 = @v1 -1 ;
     end while ;
 end;
 //
 delimiter ;


(3)游标是使用

drop procedure if exists test_cursor ;
-- delimiter表示以//结束编译
delimiter //

create procedure test_cursor(out result varchar(128))  
  begin
     -- 游标所使用变量需要在定义游标之前申明
     declare id int(11);
     declare name varchar(20);
     -- 遍历数据结束标志 注意位置顺序
     DECLARE done INT DEFAULT FALSE;
     -- 注意用别名 因为id在上面已经有定义所以需要使用表的别名区别
     declare cur_test CURSOR for select t.id,t.name from test t;
     -- 将结束标志绑定到游标 
     DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
     open cur_test;
          repeat
             fetch cur_test into id, name;
	     select id ;
	     -- concat_ws函数用逗号后面的参数隔开 concat_ws(',','12','33','332') --> 12,33,332
             select concat_ws(',',result,id,name) into result ;
          until done
	  end repeat;
      close cur_test;  
      
      select result ;
 end;
 //
 delimiter ;


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