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触发器经常用于加强数据的完整性约束和业务规则等。在MySQL与SQL操作中经常会用到,下文中国就为大家讲述MySQL与SQL的触发器的不同写法,希望对大家能够有所帮助。
触发器作用:
当在SQL、MySQL数据库中一张表中插入一条记录时,触动触发器,使同一数据库的另一张表插入相同记录。
在学习的过程中,发现两者的写法是不同的。
1、在SQL中建立两张表sql_test,sql_tem。(两张表的字段是一样的)
复制代码 代码如下:
create table sql_test
(
id int,
name varchar(16)
)
create table sql_tem
(
id int,
name varchar(16)
)
复制代码 代码如下:
/*SQL的触发器写法*/
create trigger insert_sql_test on sql_test
for insert
as
insert into sql_tem
select * from inserted
go
/*SQL的触发器写法*/
2、在MySQL中建立两张表mysql_test,mysql_tem。(两张表的字段是一样的,建表语句与上面的类似)
复制代码 代码如下:
/*MySQL的触发器写法*/
delimiter//
create trigger insert_mysql_test before insert on test
for each row
begin
insert into tem set id = new id , name = new name;
/*new后面的id,name是test表的字段名*/
end
//
关于MySQL与SQL的触发器的不同写法就为大家总结出来这么多,这些经验都是细心人士从平时的工作中总结出的,所以啊,还需要大家在工作中细心去发现,会有意想不到的惊喜哦。
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