通過時間戳組合條件並有條件地求和不同的列

Question

我試圖選擇一些交通流量數據併爲不同的交通方向創建總和，並在60秒的時間段內進行分組。簡表如下（時間戳是Unix紀元）：

Timestamp  Source  Destination Count 
1    inside  outside   5 
2    inside  outside   6 
3    outside inside   7 
65    inside  inside   4 
66    inside  outside   6 
72    inside  outside   7 

當前查詢（它的鏟裝，但沒有關於任何方向）

SELECT sum(count) AS total FROM table GROUP BY round(timestamp/60) 

這讓我對每個總數60秒「水桶」狀

Count 
18 
10 
7 

現在，在這裏我迷路了（我可以在客戶端代碼做到這一點，但我還挺喜歡與SQL如果可能這樣做）。我想有一個內部調用的入口，每個內部的source和dest作爲外部，一個叫outbound的外部行，外部的source和inside作爲dest，以及一個叫inside的行，source和dest都在裏面。依然由60秒桶分組。即什麼，我想回去是：

Inbound Outbound Internal 
    7  11  0 
    0   6  4 
    0   7  0 

我的SQL foo是弱，我真的不知道從哪裏開始（我懷疑我需要一個子查詢，但我不知道如何構建它）。

Answer 1

你應該真正能夠做一個支點：

SELECT SUM(count) AS total 
    , SUM(CASE 
       WHEN Source = 'outside' 
        AND Destination = 'inside' 
        THEN count -- Use 1 if you only want to count each row 
       ELSE 0 END) AS [Inbound] 
    , SUM(CASE 
       WHEN Source = 'inside' 
        AND Destination = 'outside' 
        THEN count 
       ELSE 0 END) AS [Outbound] 
    , SUM(CASE 
       WHEN Source = 'inside' 
        AND Destination = 'inside' 
        THEN count 
       ELSE 0 END) AS [Internal] 
FROM table 
GROUP BY round(timestamp/60) 

Answer 2

SELECT 
    round(timestamp/60)    AS bucket, 
    SUM(
    CASE WHEN source = 'inside' AND destination = 'outside' 
     THEN count ELSE 0 
    END 
)        AS outbound, 
    SUM(
    CASE WHEN source = 'outside' AND destination = 'inside' 
     THEN count ELSE 0 
    END 
)        AS inbound, 
    SUM(
    CASE WHEN source = 'inside' AND destination = 'inside' 
     THEN count ELSE 0 
    END 
)        AS internal 
FROM 
    yourTable 
GROUP BY 
    round(timestamp/60)