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
[解决办法]
where 语句能带程序吗？ 没有用过
[解决办法]
SELECT * FROM Table1
WHERE id= '2 ' AND
(T2 IS NULL and T1= '2006-12-12 ' or T2= '2006-12-12 ')
[解决办法]
好像不能这么用吧
[解决办法]
---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
[解决办法]
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 '
[解决办法]
用CASE WHEN 作判斷吧
[解决办法]
SELECT * FROM Table1
WHERE id= '2 ' AND convert(varchar(10),isnull(T2,T1),120)= '2006-12-12 '
[解决办法]
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 ')
