select * from Item where ISNULL(name,'')='' select * from Item where name is null or datalength(name)=0
無論name=''或者name爲null都可以查到
select * from Item where ISNULL(name,'')='' select * from Item where name is null or datalength(name)=0
無論name=''或者name爲null都可以查到