聚合函數或GROUP BY子句中嵌套查詢複雜

Question

我這個例子，我需要得到基於優先級的工作/任務百分比的列表：

Priority Percentages 
----------------------- 
1   %25 
11   %10 

task_events表：

task_events_id time missing_info job_id task_index machine_id event_type user scheduling_class priority cpu_request memory_request disk_space_request different_machines_restriction 

job_id其任務可以在多行中，所以我創建了新的列task_events_id作爲PK，用於嵌套選擇以獲取每個作業和任務的信號行。然後應用此結果來獲得每項工作的優先級。我想出了這個查詢。這裏的主要概念是，我有11個優先級。優先考慮有很多工作。每個作業都被分配到一個優先級。

Select 
    tes.[priority], (tes.total_priority * 100/(select sum(tes.total_priority)from tes)) as [percentage] 
From 
    (select 
     [priority], count(*) as total_priority 
    from 
     task_events as t 
    inner join 
     (select 
       max(task_events_id) as maxid, 1 as total 
      from 
       task_events 
      group by 
       job_id, task_index) as te on t.task_events_id = te.maxid 
    group by 
     [priority]) as tes 
group by 
    tes.[priority] 

這最好的我想出了，但總的是越來越複雜，任何建議

與此查詢我得到這個錯誤：

無效的對象名稱TES「。

while it's put'tes.total_priority'on last group by。

Answer 1

如果每個優先級，你想要的整體總量的百分之它，然後使用窗口功能：

select [priority], count(*) as total_priority, 
     count(*) * 1.0/sum(count(*)) over() as ratio 
from task_events t 
group by [priority]; 

Answer 2

其實你的查詢只需要在最後group by額外領域的工作......添加tes.total_priority有.. 它沒有工作，雖然 - 代碼中刪除

-- Code removed 

，但你可以通過刪除inner join考慮這個簡單的查詢，並使用distinct代替

Select 
    tes.[priority], (tes.total_priority * 100.0/sum(tes.total_priority)) as [percentage] 
From 
    (select 
     [priority], count(*) as total_priority 
    from 
     (select 
      distinct [priority], job_id, task_index 
     from task_events) as t 
     ) as tes 
group by 
    tes.[priority], tes.total_priority 

或更多使用的窗函數

select 
    [priority], count(*) as total_priority, 
    count(*) * 100.0/sum(count(*)) over() as ratio 
from (select distinct [priority], job_id, task_index 
     from task_events) as t 
group by [priority]; 

，最後一個簡單的一個，如果job_id你所需要的計算和task_index可以從子查詢中刪除..然後子查詢可以刪除通過替換count(*)與count(distinct job_id) ..但結果可能會不同於以前的查詢取決於數據和哪一個是正確的？依賴於真正想從這些數據來實現..它只是建議，但..

select 
    [priority], count(distinct job_id) as total_priority, 
    count(distinct job_id) * 100.0/sum(count(distinct job_id)) over() as ratio 
from task_events t 
group by [priority];