如何从具有多个 ORDER BY mysql 的多个表中获取记录

Question

我有三个表，我想根据所有表的日期时间获取记录，这是我的表“用户”

id      name
1       abc
2       xyz

这是我的表“paymentHistory”

id      bookingId           userId          createdOn
1       101                 1               2020-07-10 12:11:14
2       102                 1               2020-07-11 10:31:19 
3       105                 1               2020-07-11 12:31:19 
4       109                 2               2020-07-10 11:45:32 

这是我的表“cancelPaymentHistory”

id      bookingId           userId          createdOn
1       103                 1               2020-07-07 11:31:28
2       100                 1               2020-07-11 14:31:28
3       109                 2               2020-07-08 19:28:41

这是我的表“usr_booking”

id      bookingId           userId          status          created_on
1       104                 1               Inprocess       2020-07-07 10:31:28

现在我想获取 userId='1' 的所有记录，并根据三个表的 createdOn (DESC) 我该怎么做？ 我想要查询后的结果

id      bookingId           userId          createdOn
1       100                 1               2020-07-11 14:31:28      //datetime is in desending order( data coming from cancelPaymentHistory)
2       105                 1               2020-07-11 12:31:19      // data coming from paymenthistory
3       102                 1               2020-07-11 10:31:19      // data coming from paymentHistory
4       101                 1               2020-07-10  12:11:14     // data coming from paymenthistory 
...     

我尝试使用以下代码，但给了我空的结果

DROP VIEW IF EXISTS sorted_data;

create view sorted_data as (SELECT bookingId, userId as user_id, userId,createdOn,createdOn as created_on, 'paymentHistory' as table_name FROM paymentHistory) 
UNION ALL (SELECT bookingId, userId as user_id, userId,createdOn,createdOn as created_on, 'cancelPaymentHistory' as table_name FROM cancelPaymentHistory ) 
UNION ALL (SELECT bookingId, user_id, user_id as userId ,created_on as createdOn,created_on, 'usr_booking' as table_name FROM usr_booking);

Answer 1

首先，您需要更正视图创建代码：

 DROP VIEW IF EXISTS sorted_data;
    
    CREATE VIEW sorted_data 
    AS 
    (SELECT id, booking_id, user_id,created_on, 'paymentHistory' as table_name 
     FROM paymentHistory) 
    UNION ALL 
    (SELECT id, booking_id, user_id, created_on, 'cancelPaymentHistory' as table_name 
     FROM cancelPaymentHistory ) 
    UNION ALL 
    (SELECT id, booking_id, user_id, created_on, 'usr_booking' as table_name 
    FROM usr_booking);

执行此查询后，您有视图，并且此代码返回空结果是正确的 - 它只是创建视图。 但是你需要从中做出选择。 执行这个：

SELECT *
FROM sorted_data
ORDER BY created_on

结果在这里： https://dbfiddle.uk/?rdbms=mysql_8.0&fiddle=b7e77108d633d73c7732f7d36430a6d9

但我认为你的结构不是最优的。 如果我是你，我只会制作三个表： users 、 orders和order_states 。 您将只有一张表，其中包含所有用户的订单、状态以及您可以通过简单的 SELECT 获得的所有信息。