獲取累積月度用戶根據用戶的電子郵件數

Question

我有以下查詢來獲取每月累計用戶數：

SELECT RTRIM(TO_CHAR(DATE_TRUNC('month', created_at), 'Month YYYY')) AS month, 
     SUM(COUNT(id)::int) OVER (ORDER BY DATE_TRUNC('month', created_at)) AS total, 
     SUM((email  like '%@domain%')::int) AS with_domain, 
     SUM((email not like '%@domain%')::int) AS without_domain 
FROM users 
GROUP BY DATE_TRUNC('month', created_at) 
ORDER BY DATE_TRUNC('month', created_at); 

結果如下：

[ 
    {"month"=>"October 2015", "total"=>2, "with_domain"=>1, "without_domain"=>1}, 
    {"month"=>"December 2015", "total"=>6, "with_domain"=>4, "without_domain"=>0}, 
    {"month"=>"January 2016", "total"=>13, "with_domain"=>4, "without_domain"=>3}, 
    {"month"=>"February 2016", "total"=>15, "with_domain"=>2, "without_domain"=>0}, 
    {"month"=>"March  2016", "total"=>36, "with_domain"=>15, "without_domain"=>6}, 
] 

見，total怎麼算的累積和其他人不？

我嘗試以下查詢：

SELECT RTRIM(TO_CHAR(DATE_TRUNC('month', created_at), 'Month YYYY')) AS month, 
     SUM(COUNT(id)::int)     OVER (ORDER BY DATE_TRUNC('month', created_at)) AS total, 
     SUM((email  like '%@domain%')::int) OVER (ORDER BY DATE_TRUNC('month', created_at)) AS with_domain, 
     SUM((email not like '%@domain%')::int) OVER (ORDER BY DATE_TRUNC('month', created_at)) AS without_domain 
FROM users 
GROUP BY DATE_TRUNC('month', created_at) 
ORDER BY DATE_TRUNC('month', created_at); 

但它拋出

column "users.email" must appear in the GROUP BY clause or be used in an aggregate function LINE 3: SUM((email like '%@domain%')::int) OVER (ORDER BY...^: SELECT RTRI 

並添加email到GROUP BY條款是毫無意義可言......

如何使所有累計計數（就像total一樣）？

預期的結果是一樣

[ 
    {"month"=>"October 2015", "total"=>2, "with_domain"=>1, "without_domain"=>1}, 
    {"month"=>"December 2015", "total"=>6, "with_domain"=>5, "without_domain"=>1}, 
    {"month"=>"January 2016", "total"=>13, "with_domain"=>9, "without_domain"=>4}, 
    {"month"=>"February 2016", "total"=>15, "with_domain"=>11, "without_domain"=>4}, 
    {"month"=>"March  2016", "total"=>36, "with_domain"=>26, "without_domain"=>10}, 
] 

Answer 1

只是重複窗口子句爲每個要積累版本：

SELECT RTRIM(TO_CHAR(DATE_TRUNC('month', created_at), 'Month YYYY')) AS month, 
     SUM(COUNT(id)::int) OVER (ORDER BY DATE_TRUNC('month', created_at)) AS total, 
     SUM(SUM((email  like '%@domain%')::int)) OVER (ORDER BY DATE_TRUNC('month', created_at)) AS with_domain, 
     SUM(SUM((email not like '%@domain%')::int)) OVER (ORDER BY DATE_TRUNC('month', created_at)) AS without_domain 
FROM users 
GROUP BY DATE_TRUNC('month', created_at) 
ORDER BY DATE_TRUNC('month', created_at); 

Answer 2

基於OP改寫評論

使用窗口函數與爲了休息AGGS爲好。同樣如果你使用相同的窗口，最好從這裏的主要部分取出它：

SELECT distinct RTRIM(TO_CHAR(DATE_TRUNC('month', created_at), 'Month YYYY')) AS month, 
     SUM(COUNT(id)::int) OVER w AS total, 
     SUM((email  like '%@domain%')::int) OVER w AS with_domain, 
     SUM((email not like '%@domain%')::int) OVER w AS without_domain 
     , DATE_TRUNC('month', created_at) --added for sorting 
FROM users 
WINDOW W AS (PARTITION BY DATE_TRUNC('month', created_at) ORDER BY DATE_TRUNC('month', created_at)) 
ORDER BY DATE_TRUNC('month', created_at); 

Answer 3

首先得到每月的分組計數，然後得到運行總和。

SELECT month, 
     SUM(total) OVER (ORDER BY month) as total, 
     SUM(with_domain) OVER (ORDER BY month) AS with_domain, 
     SUM(without_domain) OVER (ORDER BY month) AS without_domain 
FROM (SELECT RTRIM(TO_CHAR(DATE_TRUNC('month', created_at), 'Month YYYY')) AS month, 
     COUNT(*) AS total, 
     SUM((email  like '%@domain%')::int) AS with_domain, 
     SUM((email not like '%@domain%')::int) AS without_domain 
     FROM users 
     GROUP BY RTRIM(TO_CHAR(DATE_TRUNC('month', created_at), 'Month YYYY')) 
     ) t 
ORDER BY month;