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/*----------------------------------------------------------------
-- Author  :feixianxxx(poofly)
-- Date    :2010-04-20 20:10:41
-- Version:
--      Microsoft SQL Server 2008 (SP1) - 10.0.2531.0 (Intel X86) 
Mar 29 2009 10:27:29 
Copyright (c) 1988-2008 Microsoft Corporation
Enterprise Evaluation Edition on Windows NT 6.1 <X86> (Build 7600: )
-- CONTENT£ºSQL SERVERÖÐÒ»Ð©ÌØ±ðµØ·½µÄÌØ±ð½â·¨
----------------------------------------------------------------*/
 
--1.¹ØÓÚwhereɸѡÆ÷ÖгöÏÖÖ¸¶¨ÐÇÆÚ¼¸µÄÇó½â
 
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create table test_1
(
id int,
value varchar(10),
t_time datetime
)
insert test_1 
select 1,'a','2009-04-19' union 
select 2,'b','2009-04-20' union 
select 3,'c','2009-04-21' union 
select 4,'d','2009-04-22' union 
select 5,'e','2009-04-23' union 
select 6,'f','2009-04-24' union 
select 7,'g','2009-04-25' 
go
ÎÒÃÇÒ»°ãͨ¹ý datepart(weekday )½øÐÐÇó½â£¬±ÈÈçÇó½âÐÇÆÚµÄ¼Ç¼
select * from test_1
where DATEPART(WEEKDAY,t_time+@@DATEFIRST-1)=2
/*
id          value      t_time
----------- ---------- -----------------------
3           c          2009-04-21 00:00:00.000
*/
ÕâÀïÉæ¼°µ½ @@datefirst Õâ¸öϵͳ±äÁ¿£¬Ò»°ãÎÒÃÇÓÃÀ´µ÷½Ú²»Í¬µØ·½µÄÈÕÆÚϰ¹ß¡£
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select * from test_1 
where D


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