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   ΪÁËʹÓûùÓڳɱ¾µÄÓÅ»¯Æ÷(CBO, Cost-Based Optimizer) , Äã±ØÐë¾­³£ÔËÐÐanalyze ÃüÁî,ÒÔÔö¼ÓÊý¾Ý¿âÖеĶÔÏóͳ¼ÆÐÅÏ¢(object statistics)µÄ׼ȷÐÔ.
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     ¿ÉϧµÄÊÇORACLEÖ»¶Ô¼òµ¥µÄ±íÌṩ¸ßËÙ»º³å(cache buffering) ,Õâ¸ö¹¦Äܲ¢²»ÊÊÓÃÓÚ¶à±íÁ¬½Ó²éѯ.
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