sql ±¯¾ç

http://topic.csdn.net/u/20091008/12/a2577eba-1b5b-4e1e-ab20-0a047bf3f8d7.html?4385
1Â¥
liangCK
SQL code:
update a set
ʱ¼ä = b.ʱ¼ä
from tb1 as a
join tb2 as b
on a.¿¨ºÅ= b.¿¨ºÅ
where not exists(select * from tb2
where ¿¨ºÅ=b.¿¨ºÅ and ʱ¼ä> b.ʱ¼ä)

3Â¥
liangCK
SQL code:
update a set
ʱ¼ä = b.ʱ¼ä
from @tb1 as a
join @tb2 as b
on a.¿¨ºÅ= b.¿¨ºÅ
where not exists(select * from @tb2
where ¿¨ºÅ=b.¿¨ºÅ and ʱ¼ä< b.ʱ¼ä)



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http://topic.csdn.net/u/20091008/13/490b3e82-3e4c-4e7d-a5a1-a2632e355bd8.html?32712

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1  2008    1  2008
1  2004    1  2004

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2008  = <all  n
2004  = <all  n

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