聯合計數或加入總和 - MySQL

Question

我想結合查詢中的三個表 - 日期，潛在顧客和點擊。

的表是這樣的：

日期：

|date| 

鉛：

id|time|commission 

點擊：

id|time|commission 

表格日期只是存儲日期，用於獲取沒有點擊或導致的日期。

因此，如果我們有表中的以下數據：

日期：

2009-06-01 
2009-06-02 
2009-06-03 

鉛：

1|2009-06-01|400 
2|2009-06-01|300 
3|2009-06-03|350 

點擊：

1|2009-06-01|1 
2|2009-06-03|2 
3|2009-06-03|2 
4|2009-06-03|0 

我想獲得日期，點擊次數，由點擊產生的佣金（有點擊不給佣金），銷售線索數量，由銷售線索和佣金產生的佣金。因此，與上述我的表想獲得：

2009-06-01|1|1|2|700|701| 
2009-06-02|0|0|0|0|0 
2009-06-03|3|4|1|350|354| 

我曾嘗試用下面的工會：

SELECT 
    campaign_id, 
    commission_date, 
    SUM(click_commission) AS click_commission, 
    click, 
    SUM(lead_commission) AS lead_commission , 
    lead, 
    SUM(total_commission) as total_commission 
    FROM(
     SELECT 
      click.campaign_id AS campaign_id, 
      DATE(click.time) AS commission_date, 
      click.commission AS click_commission, 
      (SELECT count(click.id) from click GROUP BY date(click.time)) as click, 
      0 as lead_commission, 
      0 as lead, 
      click.commission AS total_commission 
     FROM click 
     UNION ALL 
     SELECT 
      lead.campaign_id AS campaign_id, 
      DATE(lead.time) AS commission_date, 
      0 as click_commission, 
      0 as click, 
      lead.commission AS lead_commission, 
      lead.id as lead, 
      lead.commission AS total_commission 
     FROM lead 
     UNION ALL 
     SELECT 
      0 AS campaign_id, 
      date.date AS commission_date, 
      0 AS click_commission, 
      0 as click, 
      0 AS lead_commission, 
      0 as lead, 
      0 AS total_commission 
     FROM date 
    ) AS foo 
    WHERE commission_date BETWEEN '2009-06-01' AND '2009-07-25' 
    GROUP BY commission_date 
    ORDER BY commission_date LIMIT 0, 10 

但是，這並不工作，以計算點擊次數和潛在客戶的兩個號碼，代碼上面給出了所有線索上適量的點擊量0。如果我移動代碼並從主表中選擇，我會在所有的點擊中獲得引導權利。我一直無法找到從查詢中獲得兩個計數的方法。

於是，我就不是一個左聯接：

SELECT 
    date.date as date, 
    count(DISTINCT click.id) AS clicks, 
    sum(click.commission) AS click_commission, 
    count(lead.id) AS leads, 
    sum(lead.commission) AS lead_commission 
FROM date 
LEFT JOIN click ON (date.date = date(click.time)) 
LEFT JOIN lead ON (date.date = date(lead.time)) 
GROUP BY date.date 
LIMIT 0 , 30 

與此查詢的問題是，如果有一個以上的點擊，或者導致一個日期，將返回預期值* 2。所以2009年-06-01它將返回1400，而不是預期的700美元，作爲牽頭佣金。

所以在UNION中，我遇到了計數問題，在左邊的連接中，它是SUM不工作。

如果可能的話，我真的想堅持UNION，但我還沒有找到一種方法從它得到兩個計數。

（這是後續的this之前的問題，但由於我沒有要求計數，因此我發佈了一個新問題。）

Answer 1

SELECT date, 
     COALESCE(lcomm, 0), COALESCE(lcnt, 0), 
     COALESCE(ccomm, 0), COALESCE(ccnt, 0), 
     COALESCE(ccomm, 0) + COALESCE(lcomm, 0), 
     COALESCE(ccnt, 0) + COALESCE(lcnt, 0) 
LEFT JOIN 
     (
     SELECT date, SUM(commission) AS lcomm, COUNT(*) AS lcnt 
     FROM leads 
     GROUP BY 
       date 
     ) l 
ON  l.date = d.date 
LEFT JOIN 
     (
     SELECT date, SUM(commission) AS ccomm, COUNT(*) AS ccnt 
     FROM clicks 
     GROUP BY 
       date 
     ) с 
ON  c.date = d.date 
FROM date d 

Answer 2

，我使用的代碼，從建議修建從Quassnoi：

SELECT date, 
     COALESCE(ccomm, 0) AS click_commission, COALESCE(ccnt, 0) AS click_count, 
     COALESCE(lcomm, 0) AS lead_commision, COALESCE(lcnt, 0) AS lead_count, 
     COALESCE(ccomm, 0) + COALESCE(lcomm, 0) as total_commission 
FROM date d 
LEFT JOIN 
     (
     SELECT DATE(time) AS lead_date, SUM(commission) AS lcomm, COUNT(*) AS lcnt 
     FROM lead 
     GROUP BY 
       lead_date 
     ) l 
ON  lead_date = date 
LEFT JOIN 
     (
     SELECT DATE(time) AS click_date, SUM(commission) AS ccomm, COUNT(*) AS ccnt 
     FROM click 
     GROUP BY 
       click_date 
     ) с 
ON  click_date = date