AS400 Db2400 SQL查询或条件

Question

我正在对下面的数据进行查询

A       B           C           D   E
-----   --------    --------    --- ---
1       20140911    20140916    HPS  32
2       20140901    20140901    PLV   8
3       20140901    20140903    HPS  24

当我运行此查询时

select A, B, C, D, E 
from TABLE1 where (A = '1') and
(
    ( B >= 20140915 AND C <= 201401012 ) 
    OR 
    ( B < 20140915 AND C > 201401012 ) 
    OR 
    ( C > 201401012 AND B <= 201401012 AND B >= 20140915 ) 
    OR 
    ( C >= 20140915 AND C <= 201401012 AND B < 20140915 ) 
)

作为输出我得到了

A       B           C           D   E
-----   --------    --------    --- ---
1       20140911    20140916    HPS  32

在查询时我添加一个条件（ AND D ='HPS'），如下所示

select A, B, C, D, E from TABLE1 where (A = '1' AND D = 'HPS')
and
(
    ( B >= 20140915 AND C <= 201401012 ) 
    OR 
    ( B < 20140915 AND C > 201401012 ) 
    OR 
    ( C > 201401012 AND B <= 201401012 AND B >= 20140915 ) 
    OR 
    ( C >= 20140915 AND C <= 201401012 AND B < 20140915 ) 
)

它不会返回任何输出。我无法理解为什么会这样。