需求:從學(xué)生表中查詢(xún)出所有姓名和班級(jí)都相同的學(xué)生信息。
SQL:select distinct name,class,count(*) as recordcount from student group by name,class having count(*)>1;
SQL:select distinct name,class,count(*) as recordcount from student group by name,class having count(*)>1;