Question

我希望能够找出每月的平均值

目前我的代码是

fred = String.Format("{0}{1}{2}{1}{0}", LeftBrkt, RghtBrkt, fred);

我基本上需要它

SELECT 
    company, 
    COUNT(company) AS 'count'
FROM Information
GROUP BY company

我希望结果看起来像这样

SELECT company, 
       count(company) as 'count'
       avg(count(company)) per month as 'average'
FROM Information
group by company

Answer 1

一种非常简单的方法是先按公司和月计算，然后汇总这些数据，以获得每家公司的总数和平均值。

select
  company,
  sum(cnt) as records,
  avg(cnt) as records_per_month
from
(
  select company, year(start_date), month(start_date), count(*) as cnt
  from information
  group by company, year(start_date), month(start_date)
) agg
group by company;

但请阅读我对你问题的评论。

Answer 2

SELECT YEAR(yourDate) * 100 + MONTH(yourDate) YYMM,
        company, 
        count(company) as 'count'
        avg(count(company)) per month as 'average'
FROM Information
group by company
,YEAR(yourDate) * 100 + MONTH(yourDate)

SQL Server - 每月平均计数

2 个答案: