神马品牌网红衣校花:sql触发器问题
来源：百度文库 编辑：神马品牌网 时间：2024/05/08 19:04:05
create trigger material_delect on material
for delete
as
update table_date set m_count=m_count-1 where m_table='material'
功能是当删除material纪录时 table_date里面 m_count 减1
但我执行delete material 是只触发一次 也就是m_count-1只执行一次
请问什么回事！！谢谢
for delete
as
update table_date set m_count=m_count-1 where m_table='material'
功能是当删除material纪录时 table_date里面 m_count 减1
但我执行delete material 是只触发一次 也就是m_count-1只执行一次
请问什么回事！！谢谢
不管你删掉几条记录，一次delete只触发一次
应该 这样写
create trigger material_delect on material
for delete
as
declare i as int
set i = select count(*) from deleted
update table_date set m_count=m_count-i
where m_table='material'