MySQL存储过程例子，包含事务，参数，嵌套调用，游标，循环等

drop procedure if exists pro_rep_shadow_rs;  
delimiter |  
----------------------------------  
-- rep_shadow_rs  
-- 用来处理信息的增加，更新和删除  
-- 每次只更新上次以来没有做过的数据  
-- 根据不同的标志位  
-- 需要一个输出的参数，  
-- 如果返回为0，则调用失败，事务回滚  
-- 如果返回为1，调用成功，事务提交  
--  
-- 测试方法  
-- call pro_rep_shadow_rs(@rtn);  
-- select @rtn;  
----------------------------------  
create procedure pro_rep_shadow_rs(out rtn int)  
begin  
    -- 声明变量，所有的声明必须在非声明的语句前面  
    declare iLast_rep_sync_id int default -1;  
    declare iMax_rep_sync_id int default -1;  
    -- 如果出现异常，或自动处理并rollback,但不再通知调用方了  
    -- 如果希望应用获得异常，需要将下面这一句，以及启动事务和提交事务的语句全部去掉  
    declare exit handler for sqlexception rollback;  
    -- 查找上一次的  
    select eid into iLast_rep_sync_id from rep_de_proc_log where tbl='rep_shadow_rs';  
    -- 如果不存在，则增加一行  
    if iLast_rep_sync_id=-1 then  
      insert into rep_de_proc_log(rid,eid,tbl) values(0,0,'rep_shadow_rs');  
      set iLast_rep_sync_id = 0;  
    end if;  
      
    -- 下一个数字  
    set iLast_rep_sync_id=iLast_rep_sync_id+1;  
    -- 设置默认的返回值为0：失败  
    set rtn=0;  
      
    -- 启动事务  
    start transaction;  
    -- 查找最大编号  
    select max(rep_sync_id) into iMax_rep_sync_id from rep_shadow_rs;  
    -- 有新数据  
    if iMax_rep_sync_id>=iLast_rep_sync_id then  
        -- 调用  
        call pro_rep_shadow_rs_do(iLast_rep_sync_id,iMax_rep_sync_id);  
        -- 更新日志  
        update rep_de_proc_log set rid=iLast_rep_sync_id,eid=iMax_rep_sync_id where tbl='rep_shadow_rs';  
    end if;  
      
    -- 运行没有异常，提交事务  
    commit;  
    -- 设置返回值为1
    set rtn=1;  
end;  
|  
delimiter ;  
drop procedure if exists pro_rep_shadow_rs_do;  
delimiter |  
---------------------------------  
-- 处理指定编号范围内的数据  
-- 需要输入2个参数  
-- last_rep_sync_id 是编号的最小值  
-- max_rep_sync_id 是编号的最大值  
-- 无返回值  
---------------------------------  
create procedure pro_rep_shadow_rs_do(last_rep_sync_id int, max_rep_sync_id int)  
begin  
    declare iRep_operationtype varchar(1);  
    declare iRep_status varchar(1);  
    declare iRep_Sync_id int;  
    declare iId int;  
    -- 这个用于处理游标到达最后一行的情况  
    declare stop int default 0;  
    -- 声明游标  
    declare cur cursor for select id,Rep_operationtype,iRep_status,rep_sync_id from rep_shadow_rs where rep_sync_id between last_rep_sync_id and max_rep_sync_id;  
    -- 声明游标的异常处理，设置一个终止标记  
    declare CONTINUE HANDLER FOR SQLSTATE '02000' SET stop=1;  
      
    -- 打开游标  
    open cur;  
      
    -- 读取一行数据到变量  
    fetch cur into iId,iRep_operationtype,iRep_status,iRep_Sync_id;  
    -- 这个就是判断是否游标已经到达了最后  
    while stop <> 1 do
        -- 各种判断  
        if iRep_operationtype='I' then  
            insert into rs0811 (id,fnbm) select id,fnbm from rep_shadow_rs where rep_sync_id=iRep_sync_id;  
        elseif iRep_operationtype='U' then  
        begin  
            if iRep_status='A' then  
                insert into rs0811 (id,fnbm) select id,fnbm from rep_shadow_rs where rep_sync_id=iRep_sync_id;  
            elseif iRep_status='B' then  
                delete from rs0811 where id=iId;  
            end if;  
        end;  
        elseif iRep_operationtype='D' then  
            delete from rs0811 where id=iId;  
        end if;   
          
        -- 读取下一行的数据   
        fetch cur into iId,iRep_operationtype,iRep_status,iRep_Sync_id;  
    end while; -- 循环结束  
    close cur; -- 关闭游标  
end;  
use testprocedure;
delimiter //

create procedure simpleproce1 (out par1 int)
begin
select count(*) into par1 from proce;
end
//
delimiter ;
call simpleproce1(@a);
select @a;
#<2>,每次只有单一的行可以被取回select id,name into par1,par2 from proce LIMIT 1;中的LIMIT 1;
use testprocedure;
delimiter //
DROP procedure IF EXISTS simpleproce2
create procedure simpleproce2 (out par1 int,out par2 char(30))
begin
select id,name into par1,par2 from proce LIMIT 1;
end
//
delimiter ;
call simpleproce2(@a,@b);
select @a,@b;

## *********second test,function************
#<3>
delimiter //
DROP FUNCTION IF EXISTS hello
//
create function hello(s char(20)) returns char(50)
return concat('Hello, ',s,'!');
//
delimiter ;
select hello('world');
show create function testprocedure.helloG
#它返回子程序的特征，如数据库，名字，类型，创建者及创建和修改日期
show function status like 'hello'G
#<4>
#注意name不能和字段名相同
delimiter //
DROP procedure IF EXISTS test //
CREATE PROCEDURE test ()
BEGIN
    DECLARE name VARCHAR(5) DEFAULT 'bob';
    DECLARE newname VARCHAR(5);
    DECLARE xid INT;
   
    SELECT name,id INTO newname,xid
      FROM proce WHERE name = name;
    SELECT newname;
END;
//
call test1() //
#***
delimiter //
DROP procedure IF EXISTS test2 //
CREATE PROCEDURE test2 ()
BEGIN
   
    DECLARE newname VARCHAR(5);
    DECLARE xid INT;
   
    SELECT name,id INTO newname,xid
      FROM proce limit 1;
    SELECT newname,xid;
END;
//
call test2() //
#<5>
use testprocedure;
CREATE PROCEDURE p1 () SELECT * FROM proce;
call p1();
#<6>注意此处的handler是设置SQLSTATE值，SQLWARNING是对所有以01开头的SQLSTATE代码的速记
#NOT FOUND是对所有以02开头的SQLSTATE代码的速记
#SQLEXCEPTION是对所有没有被SQLWARNING或NOT FOUND捕获的SQLSTATE代码的速记
#DECLARE CONTINUE HANDLER声明CONTINUE异常处理
#事实上这里的23000SQLSTATE是更常用的，当外键约束出错或主键约束出错就被调用了。
#当没有发生该23000异常时， select @x2的值将是null,而不是1,
#并且后面的第2个语句执行时将会报主键约束错误，此时@x2=1,@x=4,虽然第2句有了异常，但是后面的语句继续执行
#保存到数据的数据是3,test3和5,test5
use testprocedure;
delimiter //
DROP procedure IF EXISTS handlerdemo
//
create procedure handlerdemo()
begin
declare continue handler for sqlstate '23000' set @x2=1;
set @x=1;
insert into proce values(3,'test3');
set @x=2;
insert into proce values(3,'test4');
set @x=3;
insert into proce values(5,'test5');
set @x=4;
end;
//
call handlerdemo()//
select @x //
select @x2 //
## ************光标****************
#<7>光标必须在声明处理程序之前被声明，并且变量和条件必须在声明光标或处理程序之前被声明
#在这里先声明变量a,b,c,后声明cursor
create procedure curdemo()
begin
declare done int default 0;
declare a char(16);
declare b,c int;
declare cur1 cursor for select id,name from proce;
declare cur2 cursor for select id from proce2;
declare continue handler for sqlstate '02000' set done=1;
open cur1;
open cur2;
repeat
fetch cur1 into b,a;
fetch cur2 into c;
if not done then
   if b<c then
     insert into proce3 values(b,a);
   else
     insert into proce3 values(c,a);
   end if;
end if;
until done end repeat;
close cur1;
close cur2;
end
## **************** Case *******************
#<8>when ... then ;case ... end case;
delimiter //
DROP procedure IF EXISTS p13
//
create procedure p13(in par1 int)
begin
declare var1 int;
set var1=par1+1;
case var1
when 0 then insert into casetest values(17);
when 1 then insert into casetest values(18);
else insert into casetest values(19);
end case;
end;
//
call p13(-1)//
call p13(0)//
call p13(1)//
call p13(null)//

## **************** while ****************
#<9>while ... do ... end while;为了防止null的错误，set v=0是必须的
delimiter //
DROP procedure IF EXISTS p14
//
create procedure p14()
begin
declare v int;
set v=0;
while v < 5 do
      insert into casetest values (v);
      set v=v+1;
end while;
end;//
call p14()//
## ***************** repeat *****************
#<10>repeat ...until ... end repeat; 是执行后检查（until v>=5），而while是执行前检查(while v<5)
delimiter //
DROP procedure IF EXISTS p15
//
create procedure p15()
begin
declare v int;
set v=0;
repeat
    insert into casetest values(v);
    set v=v+1;
until v >=5
end repeat;
end;
//
call p15()//
## ***************** loops *****************
#<11> loop 和while一样不需要初始条件，同时和repeat一样不需要结束条件
#      loop_label: loop
#      ...
#       if .. then
#       leave loop_label
#       end if
#      end loop
delimiter //
DROP procedure IF EXISTS p16
//
create procedure p16()
begin
declare v int;
set v=0;
loop_label: loop
    insert into casetest values(v);
    set v=v+1;
    if v >=5 then
      leave loop_label;
    end if;
end loop;
end;//
call p16()//
## ***************** Labels *****************
# <12>labels标号； 注意此处的until 0=0后面没有分号“;”
delimiter //
DROP procedure IF EXISTS p17//
create procedure p17()
label_1:begin
label_2:while 0=1 do leave label_2; end while;
label_3:repeat leave label_3;until 0=0 end repeat;
label_4:loop leave label_4; end loop;
end;//
call p17()//
#<13>labels 标号结束符；
delimiter //
DROP procedure IF EXISTS p18//
create procedure p18()
label_1:begin
label_2:while 0=1 do leave label_2; end while label_2;
label_3:repeat leave label_3;until 0=0 end repeat label_3;
label_4:loop leave label_4; end loop label_4;
end label_1;//
call p18()//
#<14>leave和labels 跳出和标号;leave 使程序跳出复杂的语句
delimiter //
DROP procedure IF EXISTS p19//
create procedure p19(par char)
label_1:begin
label_2:begin
label_3:begin
if par is not null then
if par='a' then leave label_1;
else
   begin
     if par='b' then
       leave label_2;
     else
       leave label_3;
     end if;
   end;
end if;
end if;
end label_3;
end label_2;
end label_1;
//
call p19('a')//

#<15>iterate迭代，必须用leave;iterate意思是重新开始复合语句，相当于 continue
#该结果中3将不被保存到数据库表中
delimiter //
DROP procedure IF EXISTS p20//
create procedure p20()
begin
declare v int;
set v=0;
loop_label:loop
    if v=3 then
      set v=v+1;
      iterate loop_label;
    end if;
    insert into casetest values(v);
    set v=v+1;
    if v>=5 then
      leave loop_label;
    end if;
end loop loop_label;
end;//
call p20()//

#<16>Grand combination大组合
delimiter //
DROP procedure IF EXISTS p21//
create procedure p21(in par1 int,out par2 int)
language sql deterministic sql security invoker
begin
declare v int;
label goto_label;
start_label:loop
    if v=v then
      leave start_label;
    else
      iterate start_label;
    end if;
end loop start_label;
repeat
    while 1=0 do begin end;
    end while;
until v=v
end repeat;
goto goto_label;

end;
//
call p21()//
## **************** trigger ***************************
#<17>
use testprocedure;
CREATE TABLE trig1(a1 int);
CREATE TABLE trig2(a2 int);
CREATE TABLE trig3(a3 int not null AUTO_INCREMENT PRIMARY KEY);
CREATE TABLE trig4(
a4 INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
b4 INT DEFAULT 0
);
insert into trig3(a3) values(null),(null),(null),(null),(null),(null),(null),(null),(null),(null);
insert into trig4(a4) values(0),(0),(0),(0),(0),(0),(0),(0),(0),(0);
delimiter //
DROP trigger trigtest//
create trigger trigtest before insert on trig1
for each row begin
insert into trig2 set a2=NEW.a1;
delete from trig3 where a3=NEW.a1;
update trig4 set b4=b4+1 where a4=NEW.a1;
end;
//

delimiter ;
INSERT INTO trig1 VALUES(1), (3), (1), (7), (1), (8), (4), (4);
------ -------------------------------------------------------------------------
Drop Procedure If Exists p_report;
Delimiter forend
Create Procedure p_report
(In year Int,
In month Int,
In Id Char(10),
Out status Int)
Begin
SelectYear,
Month,
OfficeId,
OnTimeRate
FromReportByMonth
WhereOfficeId = Id And
Year = year;
End
forend
Delimiter ;