Select (Case When ((Ymrq Is Not Null) And (Huidariqi Is Not Null)) Then Huidariqi Else (Case When ((Ymrq Is Not Null) And (Huidariqi Is Null) And (Xiwangriqi Is Not Null)) Then Xiwangriqi Else Huidariqi End) End) From a_Table
是我表述有问题,我的意思是:查询语句是这样的 select * from a t when (condition) ;如果页面输入的日期不为空 且表的回答日期也不为空 那么 condition = (回答日期 >= 页面输入日期) 否则 ( 如果页面输入日期不为空且表的回答日期为空并且希望日期不为空 那么 condition = (希望日期〉= 页面输入日期)
When ((Ymrq Is Not Null) And (Huidariqi Is Not Null)) Then
Huidariqi
Else
(Case
When ((Ymrq Is Not Null) And (Huidariqi Is Null) And
(Xiwangriqi Is Not Null)) Then
Xiwangriqi
Else
Huidariqi
End) End)
From a_Table
否则 ( 如果页面输入日期不为空且表的回答日期为空并且希望日期不为空 那么 condition = (希望日期〉= 页面输入日期)