使用rownum统计count（）之后的union all 不太好使

1.语法：

select t.srtypeid,cnt,s.fullname name from
(select srtypeid,count(1) cnt
from kfgl_repeat_process_detail
where partition_month='&month'
and (partition_id_region ='&region_id' or 10 ='&region_id')
group by srtypeid
order by count(1) desc) t,sdt_servicerequesttype s
where ROWNUM<11
and t.srtypeid=s.srtypeid

得到的结果：

2.语法二：

select t2.srtypeid,t2.cnt,s.fullname name from
( select srtypeid,count(1) cnt
from report_repeat_cmplt_pro_detail h
where partition_month='&month'
and h.pro_region_id ='&region_id'
group by h.srtypeid
order by count(1) DESC
) t2,sdt_servicerequesttype s
where rownum<11
and t2.srtypeid=s.srtypeid

union all 之后：

3.语法三：

select t.srtypeid,cnt,s.fullname name from
(select srtypeid,count(1) cnt
from kfgl_repeat_process_detail
where partition_month='&month'
and (partition_id_region ='&region_id' or 10 ='&region_id')
group by srtypeid
order by count(1) desc) t,sdt_servicerequesttype s
where rownum<11
and t.srtypeid=s.srtypeid
UNION ALL
select t2.srtypeid,t2.cnt,s.fullname name from
( select srtypeid,count(1) cnt
from report_repeat_cmplt_pro_detail h
where partition_month='&month'
and h.pro_region_id ='&region_id'
group by h.srtypeid
order by count(1) DESC
) t2,sdt_servicerequesttype s
where rownum<11
and t2.srtypeid=s.srtypeid

查询结果：

语法一和语法三输入的条件是一样的，在此条件下语法三没有查询结果。语法三得到的变的混乱了。

从此貌似可以看出union all 得到的查询结果并不是单个查询结果出来之后累加在一起的？

截止发文前还是有疑问，没有完全搞清楚，希望有读者解答。