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Article #174

Re: ��ô��spl���ƶ�ƽ��

#174
From: Galaxy��VOLUNTEERS��Database
Date: Fri, 17 Jul 2009 07:44
26 lines
2064 bytes
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Select sum(Price) from Table1 where ID between b.ID and b.ID-4)/ 
iif(ID>5,5,ID)
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���ID<=5,��ô�ͽ�1��ID�еļ۸�Price�ܺͳ�������(Ҳ����ID����ֵ)
ID��һ��������,�۸������Ҫ����ļ۸���� �� �� Dem 
(Galaxy ��VOLUNTEERS��Database) �Ĵ������ᵽ: ��: �������������Ϊ����
: ��ǰ����һ���?
: http://bbs.sjtu.edu.cn/file/database/124781641449192.jpg
: Ȼ��ʹ�����²�ѯ��
: SELECT ID, Price, (Select sum(Price) from Table1 where ID between b.ID and 
: b.ID-4)/ iif(ID>5,5,ID) AS MovingAvg
: FROM Table1 AS b;
: ������£�
: http://bbs.sjtu.edu.cn/file/database/124781643649390.jpg 
:  �� �� Cissnei (СC�Ů���ʹ��Smiling 
: .................������ʡ�ԣ�

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From: Dem.bbs@bbs.sjtu.edu.cn (Galaxy��VOLUNTEERS��Database)
Newsgroups: cn.bbs.comp.database
Subject: Re: ��ô��spl���ƶ�ƽ��
Date: 17 Jul 2009 07:44:44 GMT
Organization: ��ˮ˼Դ
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