SQL Server 觸發(fā)器實例詳解

create trigger tgr_nameon table_namewith encrypion –加密觸發(fā)器 for update...as Transact-SQL

--創(chuàng)建insert插入類型觸發(fā)器if (object_id('tgr_classes_insert', 'tr') is not null) drop trigger tgr_classes_insertgocreate trigger tgr_classes_inserton classes for insert --插入觸發(fā)as --定義變量 declare @id int, @name varchar(20), @temp int; --在inserted表中查詢已經(jīng)插入記錄信息 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 '添加學生成功！';go--插入數(shù)據(jù)insert into classes values('5班', getDate());--查詢數(shù)據(jù)select * from classes;select * from student order by id; 

--delete刪除類型觸發(fā)器if (object_id('tgr_classes_delete', 'TR') is not null) drop trigger tgr_classes_deletegocreate trigger tgr_classes_deleteon classes for delete --刪除觸發(fā)as print '備份數(shù)據(jù)中……'; if (object_id('classesBackup', 'U') is not null) --存在classesBackup，直接插入數(shù)據(jù) insert into classesBackup select name, createDate from deleted; else --不存在classesBackup創(chuàng)建再插入 select * into classesBackup from deleted; print '備份數(shù)據(jù)成功！';go----不顯示影響行數(shù)--set nocount on;delete classes where name = '5班';--查詢數(shù)據(jù)select * from classes;select * from classesBackup; 

--update更新類型觸發(fā)器if (object_id('tgr_classes_update', 'TR') is not null) drop trigger tgr_classes_updategocreate trigger tgr_classes_updateon classes for updateas declare @oldName varchar(20), @newName varchar(20); --更新前的數(shù)據(jù) select @oldName = name from deleted; if (exists (select * from student where name like '%'+ @oldName + '%')) begin --更新后的數(shù)據(jù) select @newName = name from inserted; update student set name = replace(name, @oldName, @newName) where name like '%'+ @oldName + '%'; print '級聯(lián)修改數(shù)據(jù)成功！'; end else print '無需修改student表！';go--查詢數(shù)據(jù)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_columngocreate trigger tgr_classes_update_columnon classes for updateas --列級觸發(fā)器：是否更新了班級創(chuàng)建時間 if (update(createDate)) begin raisError('系統(tǒng)提示：班級創(chuàng)建時間不能修改！', 16, 11); rollback tran; endgo--測試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_nameon table_namewith encryption instead of update...as T-SQL 

if (object_id('tgr_classes_inteadOf', 'TR') is not null) drop trigger tgr_classes_inteadOfgocreate trigger tgr_classes_inteadOfon classes instead of delete/*, update, insert*/as declare @id int, @name varchar(20); --查詢被刪除的信息，病賦值 select @id = id, @name = name from deleted; print 'id: ' + convert(varchar, @id) + ', name: ' + @name; --先刪除student的信息 delete student where cid = @id; --再刪除classes的信息 delete classes where id = @id; print '刪除[ id: ' + convert(varchar, @id) + ', name: ' + @name + ' ] 的信息成功！';go--testselect * 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_messagegocreate trigger tgr_messageon student after insert, updateas raisError('tgr_message觸發(fā)器被觸發(fā)', 16, 10);go--testinsert into student values('lily', 22, 1, 7);update student set sex = 0 where name = 'lucy';select * from student order by id;

alter trigger tgr_messageon studentafter deleteas raisError('tgr_message觸發(fā)器被觸發(fā)', 16, 10);go--testdelete from student where name = 'lucy';

--禁用觸發(fā)器disable trigger tgr_message on student;--啟用觸發(fā)器enable trigger tgr_message on student;

--查詢已存在的觸發(fā)器select * from sys.triggers;select * from sys.objects where type = 'TR';--查看觸發(fā)器觸發(fā)事件select te.* from sys.trigger_events te join sys.triggers ton t.object_id = te.object_idwhere t.parent_class = 0 and t.name = 'tgr_valid_data';--查看創(chuàng)建觸發(fā)器語句exec sp_helptext 'tgr_message'; 

if ((object_id('tgr_valid_data', 'TR') is not null)) drop trigger tgr_valid_datagocreate trigger tgr_valid_dataon studentafter insertas declare @age int, @name varchar(20); select @name = s.name, @age = s.age from inserted s; if (@age  18) begin raisError('插入新數(shù)據(jù)的age有問題', 16, 1); rollback tran; endgo--testinsert 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 loggocreate table log( id int identity(1, 1) primary key, action varchar(20), createDate datetime default getDate())goif (exists (select * from sys.objects where name = 'tgr_student_log')) drop trigger tgr_student_loggocreate trigger tgr_student_logon studentafter insert, update, deleteas 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'); endgo--testinsert 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;