MySQL查询将SUM但是if语句在其他字段中

Question

我遇到mysql查询问题，我想用else if语句选择SUM，这是我的故事。

我的查询：

SELECT SUM(s.total_revenue) AS sum_revenue, m.revenue_type AS revenue_type, d.campaignid AS placement_id
FROM ox_data_summary_ad_hourly AS s
INNER JOIN ox_banners AS d ON (d.bannerid = s.ad_id) 
INNER JOIN ox_campaigns AS m ON (m.campaignid = d.campaignid) 
INNER JOIN ox_clients AS a ON (a.clientid = m.clientid) 
WHERE a.type = 0
GROUP BY placement_id
LIMIT 0 , 30

并在上面查询得到如下结果：

我想生成查询： 如果revenue_type = 4将更改值sum_revenue = value placement_id， 示例结果我想如下图所示：

感谢您的帮助。

Answer 1

您可以使用CASE表达式来获得结果：

SELECT 
    case 
        when m.revenue_type = 4 
        then d.campaignid 
        else SUM(s.total_revenue) end AS sum_revenue, 
    m.revenue_type AS revenue_type, 
    d.campaignid AS placement_id
FROM ox_data_summary_ad_hourly AS s
INNER JOIN ox_banners AS d 
    ON (d.bannerid = s.ad_id) 
INNER JOIN ox_campaigns AS m 
    ON (m.campaignid = d.campaignid) 
INNER JOIN ox_clients AS a 
    ON (a.clientid = m.clientid) 
WHERE a.type = 0
GROUP BY placement_id
LIMIT 0 , 30

Answer 2

当m.revenue_type = 4时的SELECT情况然后d.campaignid否则SUM（s.total_revenue）AS sum_revenue end，m.revenue_type AS revenue_type，d.campaignid AS placement_id 来自ox_data_summary_ad_hourly AS INNER JOIN ox_banners AS d ON（d.bannerid = s.ad_id） INNER JOIN ox_campaigns AS m ON（m.campaignid = d.campaignid） INNER JOIN ox_clients AS ON（a.clientid = m.clientid） WHERE a.type = 0 GROUP BY placement_id 限制0,30