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Select avg (unitprice) //´Ó±íÖÐÑ¡ÔñÇóunitpriceµÄƽ¾ùÖµ
from products
Where categoryid = ‘8’
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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
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