订单日期范围内的SQL客户订单查询

Question

我试图得到一份订单报告，不仅返回客户订单总数，还返回三个附加字段，其中包含第一个和最后一个订单的日期以及范围第一个和最后为了

下面的查询

之间

SELECT customers.name, 
    customers.customer_id, 
    COUNT(orders.order_id) AS Orderscount 
    FROM customers 
    JOIN orders ON customers.customer_id = orders.customer_id 
    GROUP BY customers.name, 
      customers.customer_id      
     HAVING Orderscount >= 2 
     ORDER BY Orderscount DESC 

（以天为单位）返回名称，CUSTOMER_ID和订单总数的计数表。

问题是，如何添加此查询以获取first_order，last_order和两者之间的日期范围的日期？

我正在使用SQLite。

Answer 1

使用MIN和MAX获得第一和最后订购日期和julianday()计算范围：

SELECT customers.name, 
    customers.customer_id, 
    COUNT(orders.order_id) AS Orderscount, 
    MIN(col_name) AS firstOrder, 
    MAX(col_name) AS lastOrder, 
    ROUND(julianday(MAX(col_name)) - julianday(MIN(col_name))) AS range 
FROM customers 
JOIN orders ON customers.customer_id = orders.customer_id 
GROUP BY customers.name, 
     customers.customer_id      
HAVING Orderscount >= 2 
ORDER BY Orderscount DESC