select a.ID,a.FullName,b.Score from StudentInfo a left join StudentScore on a.ID=b.SIDselect a.ID,a.FullName,b.Score from StudentInfo a
select a.ID,a.FullName,b.Score from StudentInfo a left join StudentScore on a.ID=b.SIDselect a.ID,a.FullName,b.Score from StudentInfo a