效率问题
高手指点一下,那种写法的语句执行效率更高!
delete from t_BusinessInfoPic where BusinessInfoID in ( select ID from t_BusinessInfo where MemberID = 变量)
delete t_BusinessInfoPic from t_BusinessInfo,t_BusinessInfoPic where t_BusinessInfo.MemberID=1 and t_BusinessInfoPic.BusinessInfoID=t_BusinessInfo.id
------解决方案--------------------第二种吧,不太确定
好象用in效率低些
------解决方案--------------------第二种
------解决方案--------------------第一种方法会导致全表扫描
------解决方案--------------------看一下执行计划啊。
------解决方案--------------------第2种