mysql 存储过程事例
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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