SQL Server 触发器实例详解

# 创建instead of触发器

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--testselect * from student order by id;select * from classes;delete classes where id = 7; 

# 显示自定义消息raiserror

if (object_id('tgr_message', 'TR') is not null) drop trigger tgr_messagegocreate trigger tgr_messageon student after insert, updateas raisError('tgr_message触发器被触发', 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;

# 修改触发器

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

# 启用、禁用触发器

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

# 查询创建的触发器信息

--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 ton t.object_id = te.object_idwhere t.parent_class = 0 and t.name = 'tgr_valid_data';--查看创建触发器语句exec sp_helptext 'tgr_message'; 

# 示例，验证插入数据

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 lt; 18) begin raisError('插入新数据的age有问题', 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;

# 示例，操作日志

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;

以上所述是小编给大家介绍的sql server触发器，希望对大家有所帮助，同时感谢大家一直以来对脚本之家网站的支持。

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