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1.AVG ·µ»Ø×éÖеÄƽ¾ùÖµ£¬¿ÕÖµ½«±»ºöÂÔ¡£
ÀýÈ磺use  northwind   // ²Ù×÷northwindÊý¾Ý¿â
   Go
   Select  avg (unitprice)   //´Ó±íÖÐÑ¡ÔñÇóunitpriceµÄƽ¾ùÖµ
      from  products
      Where  categoryid = ‘8’
2£® BINABY_CHECKSUM  ¿ÉÓÃÓÚ¼ì²â±íÖÐÐеĸü¸Ä
·µ»ØÖµÓɱí´ïʽµÄÔËËã½á¹ûÀàÐ;ö¶¨
ÀýÈ磺use northwind
             Go
      Create  table  tablebc(productid int,bchecksum int)   //½¨Á¢ÓÐÁ½¸öÊôÐԵıí
      Insert  into tablebc   //Ïò±íÖвåÈëÊý¾Ý
          Select  priductid,binary_checksum(*)
          from  products
    Update  products   //¸üÐÂ
      Set  productname=’oishi tofu’, unitprice=20 where  productname = ‘tofu’
  
   Update  products   //¸üÐÂ
   Set  priductname=’oishi konbu’, unitprice = 5 where priductname=’konbu’
      Update priducts     //¸üÐÂ
   Set  prodctname=’oishi genen shouyu’, unitprice =12
           Where priductname=’genen shouyu’          
     Select  productid    //Ìô³ö±ä»¯µÄÐÐ
    from tablebc
    Where exists (
Select productid from products
Where  product.productid = tablebc.productid and
binary_checksu (*) <> tablebc.bchecksum)  //±êÖ¾³ö±ä»¯µÄÐÐ
3.CHECKSUM