SQL Server 触发器

Create Trigger tgr_name
On table_name
   With encrypion –加密触发器
For  Update...
As
    Transact -Sql

/************************************************************
 * Code formatted by SoftTree SQL Assistant ?v6.0.70
 * Time: 2014-10-15 10:42:34
 ************************************************************/

--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 classes
For  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 ‘添加学生成功！‘;
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 classes
For  Delete--删除触发
As
    Print ‘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 classes
For  Update
As
    Declare @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 ‘级联修改数据成功！‘;
    End
    Else
        Print ‘无需修改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?

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 classes
For  Update
As
    --列级触发器：是否更新了班级创建时间
    If (Update(createDate))
    Begin
        Raiserror(‘系统提示：班级创建时间不能修改！‘, 16, 11);
        Rollback Tran;
    End
Go
--测试
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    = 

Create Trigger tgr_name
On table_name
   With Encryption
   Instead Of Update...
As
    T -Sql

if (object_id(‘tgr_classes_inteadOf‘, ‘TR‘) is not null)
    drop trigger tgr_classes_inteadOf
go
create trigger tgr_classes_inteadOf
on classes
    instead of delete/*, update, insert*/
as
    declare @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 student
   After 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
as
    declare @age int,
            @name varchar(20);
    select @name = s.name, @age = s.age from inserted s;
    if (@age < 18)
    begin
        raisError(‘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
as
    if ((exists (select 1 from inserted)) and (exists (select 1 from deleted)))
    begin
        insert into log(action) values(‘updated‘);
    end
    else if (exists (select 1 from inserted) and not exists (select 1 from deleted))
    begin
        insert into log(action) values(‘inserted‘);
    end
    else if (not exists (select 1 from inserted) and exists (select 1 from deleted))
    begin
        insert 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;