Question

我有2张桌子

表1

per_id | per_name

1      | joe

2      | mike


x      | xxxx

和第二张桌子

per_id | job_q

1      | 500

1      | 250

2      | 125

2      | 10

3      | 54

...

i sql第三张表我将所有job_q和按per_name分组并按job_q asc排序的

表3

per_name | job_q

joe      | 750

mike     | 135

...

如何在保持job_q顺序的同时将结果限制为特定的per_name？

Answer 1

编辑-我假设OP在谈论KDB数据库中的qsql（因为使用了q标签/标记）

像这样吗？

q)`job_q xdesc select sum job_q by per_name from (t2 lj 1!t1) where per_name in `joe`mike
per_name| job_q
--------| -----
joe     | 750
mike    | 135

假设您的表在内存中。

或者如果您想按ID进行过滤：

q)`job_q xdesc select sum job_q by per_name from (t2 lj 1!t1) where per_id=2
per_name| job_q
--------| -----
mike    | 135

Answer 2

您可以通过CTE做到这一点：

with cte as (
  select t1.per_name, sum(t2.job_q) job_q
  from table1 t1 inner join table2 t2
  on t2.per_id = t1.per_id
  group by t1.per_name
)
select * from cte
order by job_q desc
limit (
  select count(*) from cte where job_q >= (
    select job_q from cte where per_name = 'mike'
  )
);

请参见demo

SQL qyery-基于非排序值限制结果查询行

2 个答案: