TSQL分組字段

Question

我有，我用得到的一些字段的項目計數的查詢：

SELECT (SUBSTRING(p.filename,5,9))AS pub, 

    COUNT(hc.queue)AS Hold, 
    COUNT(pff.queue)AS ppf, 
    FROM Preflight_Queue p 

    LEFT OUTER JOIN (SELECT status,COUNT(*)AS queue FROM Preflight_Queue WHERE status = 4 GROUP BY status)hc on hc.status= p.status 
    LEFT OUTER JOIN (SELECT status,COUNT(*)AS queue FROM Preflight_Queue WHERE status = 2 GROUP BY status)pff on pff.status= p.status 
    group by SUBSTRING(P.filename,5,9) 

這給設定這樣的記錄：在一個單獨的表

pub   Hold  pff  
RET-S0313  14  14 
ABC-X0313  20  5 

但是（ Preflight_Status）我需要獲得兩個額外的字段（forecolor和backcolor）。

兩個表已根據論文關係的兩個字段：

preflight_queue.status = preflight_staus.id

SO我試圖執行以下操作：

SELECT（SUBSTRING（p.filename， 5,9））AS酒館，

COUNT(hc.queue)AS Hold,(hc.forecolor)as holdfc,(hc.backcolor) AS holdbc, 
COUNT(pff.queue)AS pff,(pff.forecolor)as pfffc,(pff.backcolor) AS pffbc FROM Preflight_Queue p LEFT OUTER JOIN (
       SELECT p.status,s.forecolor,s.backcolor,COUNT(*)AS queue FROM Preflight_Queue p 
       JOIN preflight_Status s on s.id = p.status WHERE p.status = 4 
       GROUP BY p.status,s.forecolor,s.backcolor 
       )hc on hc.status= p.status 
LEFT OUTER JOIN (
       SELECT p.status,s.forecolor,s.backcolor,COUNT(*)AS queue FROM Preflight_Queue p 
       JOIN preflight_Status s on s.id = p.status WHERE p.status = 2 
       GROUP BY p.status,s.forecolor,s.backcolor 
       )pff on pff.status= p.status group by SUBSTRING(P.filename,5,9),hc.forecolor,hc.backcolor,pff.forecolor,pff.backcolor 

然而，因爲我現在必須將前景色和背景色組合在一起。我得到這個結果：

pub   Hold  pff holdfc holdbc  pfffc   pffbc 

RET-S0313  14  14  null  null  null   null 
RET-S0313  null null 0x000000 0xFF99FF null   null 
ABC-X0313  20  5  null  null  null   null 
ABC-X0313  null null null  null  0x000000  0xFFCCFF 

什麼，我希望做的是擁有一切在同一行這樣的：

pub   Hold pff holdfc  holdbc  pfffc  pffbc 

RET-S0313  14  14 0x000000 0xFF99FF 0x000000 0x000000  
ABC-X0313  20  5  0x000000 0xFF99FF 0x000000 0xFFCCFF 

不知道如何取得一排？

Answer 1

相信你的第一查詢可以像這樣進行簡化：

SELECT 
SUBSTRING(filename,5,9)AS pub, 
SUM(case when status = 2 then 1 else 0 end) as hold, 
SUM(case when status = 4 then 1 else 0 end) as ppf 
FROM preflight_queue 
GROUP BY SUBSTRING(filename,5,9) 

後

其中，假設顏色和p.status之間的1對1的關係，您的要求變得更容易：

SELECT 
    SUBSTRING(p.filename,5,9)AS pub, 
    SUM(case when p.status = 2 then 1 else 0 end) as hold, 
    SUM(case when p.status = 4 then 1 else 0 end) as ppf, 
    MAX(case when s.id = 2 then s.forecolor else null end) as holdfc, 
    MAX(case when s.id = 2 then s.backcolor else null end) as holdbc, 
    MAX(case when s.id = 4 then s.forecolor else null end) as holdfc, 
    MAX(case when s.id = 4 then s.backcolor else null end) as holdbc 
FROM preflight_queue p 
inner join preflight_status s on p.status = s.id 
GROUP BY 
    SUBSTRING(filename,5,9)