触发器生效逻辑
在Before或者After之后使用INSERT,DELETE,UPDATE
触发器内情况判断
- 插入
if exists(select 1 from inserted) and not exists(select 1 from deleted)
- 删除
ELSE if exists(select 1 from deleted) and not exists(select 1 from inserted)
- 更新
ELSE if exists(select 1 from deleted) and exists(select 1 from inserted)