oracle 表内做计算再统计的SQL语句怎么写 需要算的内容如下

select count(*)
from (select 人员编搭升轿号,
sum(case
when 变动类型 = '新增' then
1
else
0
end) as 新增次数,
sum(case
when 变动类型 = '删除' then
1
else
0
end) as 删除次数
from ceshi
group by 人员编号)
where 新增次数笑唯 - 删除次数 = 1;
select max(时间), 人员编号
from ceshi
where 人员编号 in (select 人员编号
from (select 人员编号知肆,
sum(case
when 变动类型 = '新增' then
1
else
0
end) as 新增次数,
sum(case
when 变动类型 = '删除' then
1
else
0
end) as 删除次数
from ceshi
group by 人员编号)
where 新增次数 - 删除次数 = 1)
group by 人员编号;