作者icefanatic (下雨天...)
看板Database
标题[SQL ] 删除重覆的资料
时间Wed Nov 25 23:21:39 2009
请问各位高手~
我用access
table有 sale 和 overlap
两个table的栏位皆有c_id,product,s_date
我想删除sale和overlap里有重覆的资料
我下的query:
SELECT sale.c_id,sale.product,sale.s_date
FROM sale,overlap
WHERE sale.c_id <> overlap.c_id AND sale.product <> overlap.product
AND sale.s_date <> overlap.s_date
GROUP BY sale.c_id,sale.product,sale.s_date;
出来的data和sale完全一样= =
根本没删除到overlap记录的资料...
请问是哪里出错了?
恳请大家指教~
谢谢~
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1F：→ iFEELing:你可以解释一下为什麽你觉得下select可以删资料吗??? 11/26 00:50
2F：→ tkcn:可能是说 "删除搜寻结果中重复的" 意即 "不搜寻重复的" 11/26 09:05
3F：推 rushcat:排除跟删除差很多耶...XDDDD 11/26 12:14
4F：→ Antzzz:好诡异的join方法，overlap多塞几笔资料还会变多咧 11/27 18:26
5F：→ icefanatic:不好意思!是排除重覆资料的意思 11/28 00:30
6F：→ terence362:楼上中肯~ 12/08 00:18