/*建表*/
create table A(keyId int,info varchar(20))
go

insert into A(keyId,info)values(1,'a'),(2,'b'),(3,'c'),(4,'d')
go

/*创建 instead of 触发器*/
create trigger tr_A on A 
instead of delete 
as 
begin
select '禁止对表进行删除操作' ---将对表delete 全部锁定禁止操作
return;

/*
if system_user ='sa'
begin
select '禁止账户(sa)对表进行删除操作' 
return;

end
*/

end
go

delete from A 
go

select * from A 
go

truncate table A
drop table A 
go