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°à¼¶±í ½Ìʦ±í
°à¼¶ID ½ÌʦID
°à¼¶Ãû×Ö °à¼¶ID
½Ìʦ´ýÓö
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select °à¼¶ID,sum(½Ìʦ´ýÓö)
from ½Ìʦ±í
group by °à¼¶ID
order by 2 desc
SQL code:
select °à¼¶Ãû×Ö,sum(½Ìʦ´ýÓö)
from ½Ìʦ±í ,°à¼¶±í
where ½Ìʦ±í.°à¼¶ID = °à¼¶±í.°à¼¶ID
group by °à¼¶Ãû×Ö
order by 2 desc
SQL code:
select m.* , avg(n.½Ìʦ´ýÓö) ½Ìʦ´ýÓö from °à¼¶±í m , ½Ìʦ±í n where m.°à¼¶ID = n.°à¼¶ID group by m.°à¼¶ID,°à¼¶Ãû×Ö order by ½Ìʦ´ýÓö desc
ÊÇÓÃavg°É?ƽ¾ù´ýÓö°É?
²»ÊÇÓÃsum.
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