如何編寫SQL查詢來找出一年中每月至少購買兩次的客戶

Question

我有一個表，其中包含列order_id，customer_id，order_date和金額。

如何查找每年每個月至少訂購2次SQL（從1月到12月）的客戶？

Answer 1

我想你正在尋找這樣的東西

select
    order_date_year,
    customer_id
from 
(
    select  
        year(order_date) as order_date_year,
        month(order_date) as order_date_month,
        customer_id,
        count(*) as number_of_orders
    from
        tableName
    group by
        year(order_date),
        month(order_date),
        customer_id
    having
        count(*) >= 2
) as t
group by
    order_date_year,
    customer_id
having
    count(*) = 12