MySql 一个存储过程的例子

MySql 存储过程简单示例：

CREATE DEFINER=`root`@`%` PROCEDURE `proc_calculate_combo_price`(IN `comboId` VARCHAR(36), OUT `price` DOUBLE, OUT `reallyPrice` DOUBLE)
	LANGUAGE SQL
	NOT DETERMINISTIC
	CONTAINS SQL
	SQL SECURITY DEFINER
	COMMENT '计算服务套餐的价格'
BEGIN
	declare minPeriodType varchar(36);
	declare minPeriodNum INT;
	declare fetchOk INT;
	declare comboPeriodNum INT;
	declare discountRate DOUBLE;
	declare discountPrice DOUBLE;
	
	declare billUnitsId varchar(36);
	declare serviceDetailId varchar(36);
	declare value INT;
	declare unitsPrice INT;
	declare unitsPeriod varchar(36);
	declare unitsPeriodNum INT;
	
	declare optionsFlag INT;
	declare minValue INT;
	declare stepLength INT;
	declare setpPrice DOUBLE;
	
	declare combo cursor for select combo.min_period_type_id,combo.min_period_num,combo.discount_rate,combo.discount_price from srv_service_combo combo where combo.id=comboId;
	declare comboDetail cursor for select detail.options_value,detail.value,detail.service_detail_id from srv_service_combo_detail detail where detail.delete_flag=0;
	declare continue handler for NOT FOUND set fetchOk = 1;
	
	set fetchOk = 0; 
	open combo;
	combo_loop: loop  
		FETCH combo INTO minPeriodType, minPeriodNum,discountRate,discountPrice;  
			IF fetchOk=1 THEN  
				LEAVE combo_loop;  
			END IF;  
	end LOOP combo_loop;  
   close combo;
   
   select period.days_number into comboPeriodNum from srv_period_type period where period.id=minPeriodType;
	
	set fetchOk = 0;
	set price=0; 
	open comboDetail;
	detail_loop: loop  
		FETCH comboDetail INTO billUnitsId, value,serviceDetailId;  
			IF fetchOk=1 THEN  
				LEAVE detail_loop;
			ELSE
				select units.price into unitsPrice from  srv_bill_units units where units.id=billUnitsId;
				select units.period_type_id into unitsPeriod from  srv_bill_units units where units.id=billUnitsId;
				select period.days_number into unitsPeriodNum from srv_period_type period where period.id=unitsPeriod;
				select sd.options_flag into optionsFlag from srv_service_detail sd where sd.id=serviceDetailId;
				IF optionsFlag=1 then
					set price=price+unitsPrice*(comboPeriodNum/unitsPeriodNum);
				ELSE
					select sd.min_value into minValue from srv_service_detail sd where sd.id=serviceDetailId;
					select sd.step_length into stepLength from srv_service_detail sd where sd.id=serviceDetailId;
					select sd.step_price into setpPrice from srv_service_detail sd where sd.id=serviceDetailId;
					set price=price+(unitsPrice+(value-minValue)/stepLength*setpPrice)*(comboPeriodNum/unitsPeriodNum);
				end if;
			END IF;  
	end LOOP detail_loop;  
   close comboDetail;
   
   set reallyPrice=price*discountRate-discountPrice;
END