create trigger tgr_name
on table_name
with encrypion –加密触发器for update...
asTransact-SQL

--创建insert插入类型触发器
if (object_id('tgr_classes_insert', 'tr') is not null)drop trigger tgr_classes_insert
go
create trigger tgr_classes_insert
on classesfor insert --插入触发
as--定义变量declare @id int, @name varchar(20), @temp int;--在inserted表中查询已经插入记录信息select @id = id, @name = name from inserted;set @name = @name + convert(varchar, @id);set @temp = @id / 2;    insert into student values(@name, 18 + @id, @temp, @id);print '加入学生成功。';
go
--插入数据
insert into classes values('5班', getDate());
--查询数据
select * from classes;
select * from student order by id;

--delete删除类型触发器
if (object_id('tgr_classes_delete', 'TR') is not null)drop trigger tgr_classes_delete
go
create trigger tgr_classes_delete
on classesfor delete --删除触发
asprint '备份数据中……';    if (object_id('classesBackup', 'U') is not null)--存在classesBackup。直接插入数据insert into classesBackup select name, createDate from deleted;else--不存在classesBackup创建再插入select * into classesBackup from deleted;print '备份数据成功！';
go
--
--不显示影响行数
--set nocount on;
delete classes where name = '5班';
--查询数据
select * from classes;
select * from classesBackup;

--update更新类型触发器
if (object_id('tgr_classes_update', 'TR') is not null)drop trigger tgr_classes_update
go
create trigger tgr_classes_update
on classesfor update
asdeclare @oldName varchar(20), @newName varchar(20);--更新前的数据select @oldName = name from deleted;if (exists (select * from student where name like '%'+ @oldName + '%'))begin--更新后的数据select @newName = name from inserted;update student set name = replace(name, @oldName, @newName) where name like '%'+ @oldName + '%';print '级联改动数据成功！';endelseprint '无需改动student表！

'

; go --查询数据 select * from student order by id; select * from classes; update classes set name = '五班' where name = '5班';

if (object_id('tgr_classes_update_column', 'TR') is not null)drop trigger tgr_classes_update_column
go
create trigger tgr_classes_update_column
on classesfor update
as--列级触发器：是否更新了班级创建时间if (update(createDate))beginraisError('系统提示：班级创建时间不能改动。', 16, 11);rollback tran;end
go
--測试
select * from student order by id;
select * from classes;
update classes set createDate = getDate() where id = 3;
update classes set name = '四班' where id = 7;

create trigger tgr_name
on table_name
with encryptioninstead of update...
asT-SQL

if (object_id('tgr_classes_inteadOf', 'TR') is not null)drop trigger tgr_classes_inteadOf
go
create trigger tgr_classes_inteadOf
on classesinstead of delete/*, update, insert*/
asdeclare @id int, @name varchar(20);--查询被删除的信息。病赋值select @id = id, @name = name from deleted;print 'id: ' + convert(varchar, @id) + ', name: ' + @name;--先删除student的信息delete student where cid = @id;--再删除classes的信息delete classes where id = @id;print '删除[ id: ' + convert(varchar, @id) + ', name: ' + @name + ' ] 的信息成功。';
go
--test
select * from student order by id;
select * from classes;
delete classes where id = 7;

if (object_id('tgr_message', 'TR') is not null)drop trigger tgr_message
go
create trigger tgr_message
on studentafter insert, update
as raisError('tgr_message触发器被触发', 16, 10);
go
--test
insert into student values('lily', 22, 1, 7);
update student set sex = 0 where name = 'lucy';
select * from student order by id;

alter trigger tgr_message
on student
after delete
as raisError('tgr_message触发器被触发', 16, 10);
go
--test
delete from student where name = 'lucy';

--禁用触发器
disable trigger tgr_message on student;
--启用触发器
enable trigger tgr_message on student;

--查询已存在的触发器
select * from sys.triggers;
select * from sys.objects where type = 'TR';--查看触发器触发事件
select te.* from sys.trigger_events te join sys.triggers t
on t.object_id = te.object_id
where t.parent_class = 0 and t.name = 'tgr_valid_data';--查看创建触发器语句
exec sp_helptext 'tgr_message';

if ((object_id('tgr_valid_data', 'TR') is not null))drop trigger tgr_valid_data
go
create trigger tgr_valid_data
on student
after insert
asdeclare @age int,@name varchar(20);select @name = s.name, @age = s.age from inserted s;if (@age < 18)beginraisError('插入新数据的age有问题', 16, 1);rollback tran;end
go
--test
insert into student values('forest', 2, 0, 7);
insert into student values('forest', 22, 0, 7);
select * from student order by id;

if (object_id('log', 'U') is not null)drop table log
go
create table log(id int identity(1, 1) primary key,action varchar(20),createDate datetime default getDate()
)
go
if (exists (select * from sys.objects where name = 'tgr_student_log'))drop trigger tgr_student_log
go
create trigger tgr_student_log
on student
after insert, update, delete
asif ((exists (select 1 from inserted)) and (exists (select 1 from deleted)))begininsert into log(action) values('updated');endelse if (exists (select 1 from inserted) and not exists (select 1 from deleted))begininsert into log(action) values('inserted');endelse if (not exists (select 1 from inserted) and exists (select 1 from deleted))begininsert into log(action) values('deleted');end
go
--test
insert into student values('king', 22, 1, 7);
update student set sex = 0 where name = 'king';
delete student where name = 'king';
select * from log;
select * from student order by id;