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 select datepart(yy,cdate) as 'Ô·Ý',sum(cmoney) from consumption group by datepart(yy,cdate)
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 select datepart(mm,cdate) as 'Ô·Ý',sum(cmoney) from consumption where datepart(yy,cdate)=2009 group by datepart(mm,cdate)
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select DATEPART(wk,cdate) as 'ÖÜ', sum(cmoney) from consumption group by DATEPART(wk,cdate)
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select DATEPART(dd,cdate) as 'ºÅ', sum(cmoney) from consumption  where datepart(mm,cdate)=6  group by DATEPART(dd,cdate)
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month               mm                1--12
day of year         dy                1--366
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