CREATE TABLE `retailcatalog` (
`UUID` varchar(38) NOT NULL COMMENT '唯一标识,自动生成,为主键',
`PRODUCTUUID` varchar(38) NOT NULL COMMENT '商品唯一标识,需要创建索引',
`BEGINDATE` date NOT NULL COMMENT '起始时间',
`ENDDATE` date NOT NULL COMMENT '截止时间',
`PRICE` double(19,4) NOT NULL COMMENT '销售价',
PRIMARY KEY (`UUID`),
UNIQUE KEY `UQ_RETAILCATALOG_RetailcatalogID` (`UUID`,`PRODUCTUUID`),
KEY `IX_retailcatalog_productUUID` (`PRODUCTUUID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `product` (
`UUID` varchar(38) NOT NULL,
`CODE` varchar(20) NOT NULL COMMENT '代码,需要创建索引',
`NAME` varchar(100) NOT NULL COMMENT '名称',
`ORDERPRICE` double(19,4) DEFAULT NULL COMMENT '采购价',
`SALEPRICE` double(19,4) DEFAULT NULL COMMENT '销售价(数据来源于 RETAILCATALOG 表)',
`STATE` int(11) DEFAULT NULL COMMENT '状态 (0 为使用中, 999 为已删除 )',
PRIMARY KEY (`UUID`),
UNIQUE KEY `UUID` (`UUID`),
KEY `IX_product_code` (`CODE`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
有两张表,retailcatalog和product
有一个存储过程
/*
*将 RETAILCATALOG 上的 PRICE 数据同步到 PRODUCT 表上的 SALEPRICE
*/
drop procedure if exists proc_product_saleprice_state_update;
create procedure proc_product_saleprice_state_update(
in nowday date
)
begin
update
product p, retailcatalog r
set
p.SALEPRICE=r.PRICE,p.STATE=0
where
r.PRODUCTUUID = p.UUID and nowday >= r.BEGINDATE and nowday <= r.ENDDATE;
update
product p, retailcatalog r
set
p.SALEPRICE=0,p.STATE=999
where
(r.PRODUCTUUID = p.UUID and (nowday < r.BEGINDATE or nowday > r.ENDDATE)) or
not exists(
select
1
from
retailcatalog r
where
p.UUID = r.PRODUCTUUID);
end;
a. 编写一个触发器,要求在修改销售目录( RETAILCATALOG )数据的 PRICE 之后,修改 PRODUCT 表的 SALEPRICE
b. 编写一个触发器,要求在修改商品表( PRODUCT )数据的状态( STATE )之后,如果发现 STATE 为 999 ,则删除对应的 RETAILCATALOG
以下是我写的触发器
/*
*在修改销售目录( RETAILCATALOG )数据的 PRICE 之后,修改 PRODUCT 表的 SALEPRICE
*/ DROP TRIGGER
IF
EXISTS retailcatalog_after_update_price_on_product;
CREATE TRIGGER retailcatalog_after_update_price_on_product AFTER UPDATE ON retailcatalog FOR EACH ROW
BEGIN
IF
new.PRICE <> old.PRICE THEN
UPDATE product p
SET p.SALEPRICE = new.PRICE
WHERE
p.UUID = new.PRODUCTUUID;
END IF;
END;
/*
*在修改商品表( PRODUCT )数据的状态( STATE )之后,如果发现 STATE 为 999 ,则删除对应的 RETAILCATALOG
*/
DROP TRIGGER
IF
EXISTS product_after_update_state_on_retailcatalog;
CREATE TRIGGER product_after_update_state_on_retailcatalog AFTER UPDATE ON product FOR EACH ROW
BEGIN
IF
new.STATE = 999 THEN
DELETE r
FROM
retailcatalog r
WHERE
( r.PRODUCTUUID = new.UUID AND new.STATE = 999 );
END IF;
END;
当我运行存储过程时
call proc_product_salepriceAndstate_update(CURDATE());
数据库报错
call proc_product_salepriceAndstate_update(CURDATE())
1442 - Can't update table 'retailcatalog' in stored function/trigger because it is already used by statement which invoked this stored function/trigger.
各位大神能指导下我应该如何改进吗?