SQL Server DATEDIFF() º¯Êý
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DATEDIFF() º¯Êý·µ»ØÁ½¸öÈÕÆÚÖ®¼äµÄÌìÊý¡£
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DATEDIFF(datepart,startdate,enddate)
startdate ºÍ enddate ²ÎÊýÊǺϷ¨µÄÈÕÆÚ±í´ïʽ¡£
datepart ²ÎÊý¿ÉÒÔÊÇÏÂÁеÄÖµ£º
datepart
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Äê
yy, yyyy
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qq, q
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mm, m
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dy, y
ÈÕ
dd, d
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wk, ww
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dw, w
Сʱ
hh
·ÖÖÓ
mi, n
Ãë
ss, s
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ms
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mcs
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ns
select convert(varchar,datediff(s,'2009-12-15',getdate())/3600)+'Сʱ'+
convert(varchar,datediff(s,'2009-12-15',getdate())%3600/60)
+'·ÖÖÓ'
+
convert(varchar,datediff(s,'2009-12-15',getdate())%3600%60)
+'Ãë'
Ïà¹ØÎĵµ£º
1¡¢²éѯÁ½¸öʱ¼äÖ®¼ä
select * from [tablename] where date between \'value1\' and \'value2\'
2¡¢ÏÔʾ×îºó»Ø¸´Ê±¼ä
select a.title,a.username,b.adddate from table a,(select max(adddate) adddate from table where table.title=a.title) b
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Stud_ID
Name
1
Tom
2
Jack
T_Course ±í
Course_ID
Course
1
Chinese
2
English
T_Stud_Course ±í
ID
Stud_ID
Course_ID
1
1
1
2
1
2
3
2
2
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