mysql5.6.0 的存儲過程 與 定時器 實例

1、寫mysql存儲過程應注意的幾點：

一、聲明變量（declare）時要注意字符集，用變量存儲表字段時，表字段與變量的字符編碼要一致。

二、mysql的字符合並不能用‘+’號，必須用concat函數。

三、每一個遊標必須使用不一樣的declare continue handler for not found set done=1來控制遊標的結束。

實例：

delimiter //		-- 將語句結束標誌設爲雙斜槓，默認以逗號做爲語句結束標誌
CREATE  PROCEDURE `proxy_infreeze`()
BEGIN 
DECLARE done INT DEFAULT 0; 
DECLARE proxy_infreeze_amount DECIMAL(10,2) ; -- 注意位長也要聲明，會有進位或捨棄
DECLARE customerId BIGINT ; 
DECLARE cursor_avgScore CURSOR FOR (
	SELECT SUM(update_amount) proxy_infreeze_amount,b.customer_id
	FROM customer_bill b
	WHERE bill_type =4 AND statu = 1 AND create_at > DATE_ADD(NOW(), INTERVAL -9 DAY) AND create_at < DATE_ADD(NOW(), INTERVAL -7 DAY)
	GROUP BY b.customer_id
); 
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1; -- 控制遊標的結束。
OPEN cursor_avgScore; 
FETCH  cursor_avgScore INTO proxy_infreeze_amount,customerId; 
out_loop:
	LOOP
	UPDATE customer_account SET proxy_freeze_amount =proxy_freeze_amount-proxy_infreeze_amount WHERE customer_id = customerId;  
		FETCH  cursor_avgScore INTO proxy_infreeze_amount,customerId;  
	IF done =1 THEN
				LEAVE out_loop;
	END IF;
END LOOP out_loop;
CLOSE cursor_avgScore; 
	update customer_bill set statu = 2 WHERE bill_type =4 AND statu = 1 AND create_at > DATE_ADD(NOW(), INTERVAL -9 DAY) AND create_at < DATE_ADD(NOW(), INTERVAL -7 DAY);
END // 
delimiter ;

　　

二 、 定時器

--查看定時策略是否開啓
show variables like '%event_sche%';
-- 開啓定時策略
set global event_scheduler=1;

--	建立定時任務event(事件)
create event batchDel_overdue_order_event
on schedule every 1 day starts '2016-10-01 23:50:00'
on completion preserve disable
do call batchDel_overdue_order();

--查看定時任務event(事件)，能夠查看本機全部的事件
SELECT event_name,event_definition,interval_value,interval_field,status FROM information_schema.EVENTS;

alter event batchDel_overdue_order_event on completion preserve enable;--開啓定時任務
alter event second_event on completion preserve disable;--關閉定時任務