SELECT book.name ,COUNT(*) num FROM book JOIN class ON book.name=class.name GROUP BY book.name ORDER BY num; SELECT book.name ,COUNT(*) num,class FROM book JOIN class ON book.name=class.name WHERE class='班级一' GROUP BY book.name
1. select name,count(*) as 借书数量 from a表 group by name;2: 借书情况是指什么?贴下结果
1 seletct name Name,count(*) '借书数量' from a group by name;2 班级一 每个人的借书情况 select name Name,count(*) '借书数量'from a where a.name in (select name from b where b.class='班级一')group by name; 3 班级一 总共借书 select count(*) '借书数量'from a where a.name in (select name from b where b.class='班级一');
1 seletct name Name,count(*) '借书数量' from a group by name;2 班级一 每个人的借书情况
select name Name,count(*) '借书数量'from a where a.name in (select name from b where b.class='班级一')group by name;
3 班级一 总共借书
select count(*) '借书数量'from a where a.name in (select name from b where b.class='班级一');