select top 5
B.u_name
,count(1) as '借阅册数'from lend A
join reader B on A.userid=B.userid
join book C on B.bookid=C.bookid
group by B.userid,B.u_name
order by count(1) desc
B.u_name
,count(1) as '借阅册数'from lend A
join reader B on A.userid=B.userid
join book C on B.bookid=C.bookid
group by B.userid,B.u_name
order by count(1) desc
解决方案 »
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