使用分区的oraclesql查询

我有一个疑问：

select a.name, count(distinct numClient)
from a
group by a.name;

我想添加另一列，每行将计算前面几行的总和：

JONES     3      0
SMITH     5      3
JOHN      10     8
.....
KEN       12     365

---

你能帮忙吗？。我想我必须使用分区，但我不太理解它。

假设有一列指定计算累计和的顺序，您可以使用

select name,cntClient,sum(cntClient) over(order by orderCol rows between unbounded preceding and 1 preceding) as cumCntClient
from (select a.name, count(distinct numClient) as cntClient
      from a
      group by a.name
     ) t

---

假设有一列指定计算累计和的顺序，则可以使用

select name,cntClient,sum(cntClient) over(order by orderCol rows between unbounded preceding and 1 preceding) as cumCntClient
from (select a.name, count(distinct numClient) as cntClient
      from a
      group by a.name
     ) t

---

您根本不需要子查询：

select a.name, count(distinct numClient),
       (sum(count(distinct numClient)) over (order by count(distinct numClient)) -
        count(distinct numClient)
       ) as running_sum
from a
group by a.name;

---

您根本不需要子查询：

select a.name, count(distinct numClient),
       (sum(count(distinct numClient)) over (order by count(distinct numClient)) -
        count(distinct numClient)
       ) as running_sum
from a
group by a.name;

---

您是否有一列指定顺序？您是否有一列指定顺序？这里的orderCol是什么？计算累计和的顺序..可以是

cntClient

，根据示例显示这里的orderCol是什么？计算累计和的顺序..根据所示示例可以是

cntClient