Oracle Apex中使用Pivot显示空值和n的奇怪结果

我用Apex 4.2.6运行oracle 11g。我试图运行一个脚本，但在apex中返回空值，但在SQLDeveloper中显示正确的结果

  select "ENG_ID","ENG_ID1","roles","Region","1","2","3","4","5","6","7","8","9","10","11","12","13","14","15"    ,"16","17","18","19","20","21","22","23","24","25","26","27","28","29","30","31" from (
   select M.ENG_ID as ENG_ID,
M.ENG_ID as ENG_ID1,
e.ROLE_ID as "roles",
  e.REGION_AREA_ID as "Region",
EXTRACT(DAY FROM M.MS_DATE) as DOM,
   MD.MD_ID 
      --MD.JOB_TYPE_ID
from MD_TS_DETAIL MD,
MD_TS_MAST M,MAN_ENGINEERS e
where
m.eng_id = 542 and
M.ENG_ID = e.ENG_ID and
M.MAST_ID=MD.MD_ID and
M.MS_DATE between trunc(sysdate,'MM') and last_day(sysdate)
)pivot (
max(MD_ID) 
for DOM in (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31)
)

这给了我正确的计算结果

SQL开发视图

但是在Apex中运行相同的脚本会得到null

顶点视图

---

我完全被难住了，你们有什么想法吗？

好的，在检查了max记录了什么之后，这两个记录都直接记录在APEX和数据库上。 . 在SQL workshop>selected MD\u TS\u MAST>statistics>Analysis>estimate statistics中更改为100%>next>finish

---

所有的记录都回来了。我不知道为什么apex没有直接从数据库运行。因此，基本上，如果在SQL developer中执行插入操作，您必须通过分析进行更新。

我想我知道了一些事情，但仍然很困惑，我直接在数据库的MD_TS_MAST中运行select max（MAST_ID），得到了90367。在APEX中运行相同的脚本我得到69738正如我所知，APEX直接从数据库运行。如果您在IDE中进行了插入，可能只是忘记了提交？否则，我不知道该怎么解释。