查询列出在日期之间订购和未在日期之间订购的客户

Question

我有两个表 customers 其中有很多 orders.

我想列出在两个日期之间订购但不在以后的日期（之后）订购的客户。我想弄清楚哪些客户没有 return。

我可以编写查询，在其中列出在不同日期之间订购的客户。

SELECT
    "customers".* 
FROM
    "customers"
    LEFT JOIN orders ON orders.customer_id = customers.ID 
    AND orders.deleted_at IS NULL 
    AND ( orders.created_at BETWEEN '2020/06/05' AND '2020/06/13' ) 
WHERE
    ( orders.customer_id IS NOT NULL ) 
GROUP BY
    customers.ID

我也可以写查询，它将给我一个在日期之间没有订购的列表

SELECT
    "customers".* 
FROM
    "customers"
    LEFT JOIN orders ON orders.customer_id = customers.ID 
    AND orders.deleted_at IS NULL 
    AND ( orders.created_at BETWEEN '2020/06/16' AND '2020/06/18' ) 
WHERE
    ( orders.customer_id IS NULL ) 
GROUP BY
    customers.ID

但无法弄清楚如何在一次查询中获得此列表。

我的最后一个查询（不起作用）

SELECT  
"customers".*
FROM "customers" 

LEFT JOIN "orders" ON "orders"."customer_id" = "customers"."id" AND "orders"."deleted_at" IS NULL 

WHERE 

-- LAST WEEK
AND (orders.created_at BETWEEN '2020/06/05' AND '2020/06/13' AND orders.customer_id IS NOT NULL) 
-- NOT ORDERED TODAY 
AND (orders.created_at BETWEEN '2020/06/16' AND '2020/06/18' AND orders.customer_id IS NULL)

GROUP BY customers.id

Answer 1

请试试这个，如果它对你不起作用或者你想要对它的任何部分进行解释，请在评论中告诉我。

with params as (
  select '2020/06/05' as r1start, '2020/06/13' as r1end, 
         '2020/06/16' as r2start, '2020/06/18' as r2end
) ordersinfo as (
  SELECT customers.id,
         MAX(CASE 
               WHEN orders.created_at between p.r1start and p.r1end then 1
               ELSE 0
             END) as r1order,
         MAX(CASE 
               WHEN orders.created_at between p.r2start and p.r2end then 1
               ELSE 0
             END) as r2order
    FROM customers
    CROSS JOIN params p
    JOIN orders 
      ON orders.customer_id = customers.ID 
     AND orders.deleted_at IS NULL 
     AND ( orders.created_at BETWEEN p.r1start AND p.r2end ) 
  GROUP BY customers.ID
)
select c.*
  from ordersinfo o
  join customers c on c.id = o.id 
 where o.r1order = 1 and o.r2order = 0;

Answer 2

PostgreSQL 允许您 combine 查询结果 - 在本例中您似乎在寻找 INTERSECT。它为您提供了一组匹配这两个查询的记录。您可以直接使用第一个并将其结果与另一个相交，而无需重写任何内容：

SELECT
    *
FROM --here goes your first query
   (SELECT
        "customers".* 
    FROM
        "customers"
        LEFT JOIN orders ON orders.customer_id = customers.ID 
        AND orders.deleted_at IS NULL 
        AND ( orders.created_at BETWEEN '2020/06/05' AND '2020/06/13' ) 
    WHERE
        ( orders.customer_id IS NOT NULL ) 
    GROUP BY
        customers.ID
    ) a
INTERSECT --here you put your other query
   (SELECT 
        "customers".* 
    FROM
        "customers"
        LEFT JOIN orders ON orders.customer_id = customers.ID 
        AND orders.deleted_at IS NULL 
        AND ( orders.created_at BETWEEN '2020/06/16' AND '2020/06/18' ) 
    WHERE
        ( orders.customer_id IS NULL ) 
    GROUP BY
        customers.ID 
    );

如果您想保留重复项，请将它们与 INTERSECT ALL 合并。

您可以通过多种方式重写您的查询以一次性获得您想要的结果，无需此机制，但可以使用 UNION、INTERSECT 和 [=15= 组合结果] 在这种情况下是一个非常有用的工具，当您努力想出具有一组条件的单个查询时，它会为您提供所需的结果。值得注意的是，在一定规模上，性能可能会成为比查询优化难度更大的问题。

Answer 3

您可以使用 EXISTS 和 NOT EXISTS 的组合：

select cust.* 
  from "customers" cust
where
      exists 
           (select null 
              from orders ord1
             where ord1.customer_id = cust.id
               and ord1.created_at between date '2020-06-05' and date '2020-06-13'
           )              
  and not exists 
          ( select null 
              from orders ord2
             where ord2.customer_id = cust.id
               and ord2.created_at between date '2020-06-16' and date '2020-06-18'
          ) ;

这应该会很好地执行，特别是如果您有索引订单(customer_id, created_at)。

查询列出在日期之间订购和未在日期之间订购的客户

Query listing customers who ordered between dates and not ordered between dates

postgresql

date

between