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作者 Oracle SQL优化,看帖子!
gaoxt1983





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于 2006-09-05 14:43 user profilesend a private message to usersearch all posts byselect and copy to clipboard. 
ie only, sorry for netscape users:-)add this post to my favorite list
select ID from education t where RESUME_ID=34 AND GRADUATE_DATE=(SELECT MAX(GRADUATE_DATE) FROM EDUCATION WHERE RESUME_ID=34)

select ID FROM EDUCATION t WHERE RESUME_ID=34 AND ROW_NUM=1 ORDER BY GRADUATE_DATE DESC
其实就是找出同一个RESUME_ID的记录中GRADUATE_DATE最大的那个,第一个估计效率不高,第二个很别扭,又没有更好的方法



作者 Re:Oracle SQL优化,看帖子! [Re:gaoxt1983]
gaoxt1983





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于 2006-09-05 14:57 user profilesend a private message to usersearch all posts byselect and copy to clipboard. 
ie only, sorry for netscape users:-)add this post to my favorite list
需求理解错了,应该是选出所有以RESUME_ID分组的GRADUATE_DATE最大的数据


作者 Re:Oracle SQL优化,看帖子! [Re:gaoxt1983]
熙城候





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于 2006-09-06 11:03 user profilesend a private message to usersearch all posts byselect and copy to clipboard. 
ie only, sorry for netscape users:-)add this post to my favorite list
路过,帮忙顶



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