select 语句中的where判断问题
表名：Table1               列名：T1，T2为datetime
id       T1                             T2
1         2007-12-13           null
2         2007-12-12           null
3         2007-12-15           2007-12-12
4         2007-12-15           null

如果T2不为空，就以T2为查询条件   否则以T1为查询条件
下面是我写的SQL语句，有错误，不知道应该怎摸写
SELECT   *   FROM   Table1
WHERE   id= '2 '   AND  
            (CASE   WHEN   T1   IS   NULL  
            THEN   T1=   '2006-12-12 '   ELSE   T2=   '2006-12-12 '   END)
id=2   和 '2006-12-12 '都是我输入的查询参数

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where 语句能带程序吗？ 没有用过
------解决方案--------------------
SELECT * FROM Table1
WHERE id= '2 ' AND
(T2 IS NULL and T1= '2006-12-12 ' or T2= '2006-12-12 ')
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好像不能这么用吧
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---try
SELECT * FROM Table1
WHERE id= '2 ' AND
T1=CASE WHEN T2 IS NULL
THEN '2006-12-12 ' ELSE T1 END AND T2 = CASE WHEN T2 IS NULL THEN T2 ELSE '2006-12-12 ' END

------解决方案--------------------
create table table1(id int, T1 datetime, T2 datetime)
insert table1 select 1, '2007-12-13 ', null
union all select 2, '2007-12-12 ', null
union all select 3, '2007-12-15 ', '2007-12-12 '
union all select 4, '2007-12-15 ', null

select * from table1
where (case when T2 is not null then T2 else T1 end)= '2006-12-12 '
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用CASE WHEN 作判斷吧
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SELECT * FROM Table1
WHERE id= '2 ' AND convert(varchar(10),isnull(T2,T1),120)= '2006-12-12 '
------解决方案--------------------
楼主看看能不能这样做:

SELECT * FROM table1
where
(t2 is not null and t2> '2006-12-12 ') or
(t2 is null and t1 = '2006-12-12 ')