Question

如何判断列中的数据是否已经更改，如果更改了就触发触发器？

假如表名为jiazu，字段有组别，项目，比赛成绩，排名
组别字段中有man，wom
项目有100，200
当比赛成绩输入数据后，就激活自动排名？
求怎么写，急
怎么写触发器

Answer 1

create table info(_id int unique identity(1,1),grade decimal(10,2);
go
insert into info(grade)values(10);
go

create trigger info_update_trigger on info for update
as
begin
declare @old_grade decimal(10,2), @new_grade decimal(10,2);
select @new_grade = n.grade,
@old_grade = o.grade
from inserted as n
inner join deleted as o on o._id=n._id;
if(@new_grade != @old_grade )
begin
print('old grade=' + convert(varchar,@old_grade));
print('new grade=' + convert(varchar,@new_grade));
print('log it');
end
end
go

update info set grade = grade + 1 where _id=1