根据单个日期列计算具有 from_date 和 to_date 的一组行

Question

我有一个 customer_audit 表，记录发生在客户表上的 INSERT 和 UPDATE。

客户审核

id	操作	时间戳	客户 ID	地址1	地址2
1	我	2024-10-05	100	链接st	1号
2	你	2024-10-06	100	链接st	2号
3	你	2024-10-07	100	连接路	2号
4	你	2024-10-08	100	连接路	数量200
5	我	2024-10-06	200	公园街	20号
6	你	2024-10-08	200	公园街	数量200

预期输出（在本例中为

address1

和

address2

）分别显示地址 1 和地址 2 的所有历史值，其中

from_date

和

to_date

根据时间戳列计算。

例如对于 customer_id 100：

客户 ID	列名称	列值	起始日期	截止日期
100	地址1	链接st	2024-10-05	2024-10-07
100	地址1	连接路	2024-10-07	null（表示列值是当前值）
100	地址2	1号	2024-10-05	2024-10-06
100	地址2	2号	2024-10-06	2024-10-08
100	地址2	数量200	2024-10-08	空

我通过稍微调整 mcwolf 的查询来解决这个问题：

select customer_id, name, 'address1' as attribute_name, address1 as "attribute_value", min(from_date) as "valid_from", max(to_date) as "valid_to"
from (
select customer_id, 
       name, 
       address1,
       "mod_timestamp" from_date,
         COALESCE(lead("mod_timestamp") over change_window, to_date('99991231', 'yyyymmdd')) to_date,
       ROW_NUMBER () OVER ( PARTITION BY customer_id, address1 ORDER BY mod_timestamp) as rownum
from customer_audit
WINDOW change_window as (PARTITION BY customer_id order by mod_timestamp)   
order by customer_id, mod_timestamp ) a
group by customer_id, name, attribute_name, "attribute_value"
order by customer_id, "valid_from";

Answer 1

...这是另一种方法...

WITH
  dates AS    -- track changes of addresses ( ..._rn = 1 )
    ( Select ca.id, customer_id, "timestamp" as ts,
             address1, Row_Number() Over(Partition By customer_id, address1 Order By id) addr1_rn,
             address2, Row_Number() Over(Partition By customer_id, address2 Order By id) addr2_rn
      From   customer_audit ca
    ) 
--    M a i n    S Q L : 
SELECT  f.customer_id, 'address1' as column_name, f.address1 as column_value, f.ts as from_date,  
        Lead(ts) Over(Partition By customer_id, 'address1' Order By id) as to_date
FROM  ( Select  * From  dates Where addr1_rn = 1 ) f
UNION ALL 
SELECT  f.customer_id, 'address2', f.address2, f.ts, 
        Lead(ts) Over(Partition By customer_id, 'address2' Order By id) as to_date
FROM  ( Select  * From  dates Where addr2_rn = 1 ) f 
ORDER BY  customer_id, column_name, from_date

/*     R e s u l t : 
customer_id column_name column_value    from_date               to_date
----------- ----------- --------------  ----------------------  ----------------------
        100 address1    link st         2024-10-05 00:00:00     2024-10-07 00:00:00
        100 address1    link road       2024-10-07 00:00:00     null
        100 address2    number 1        2024-10-05 00:00:00     2024-10-06 00:00:00
        100 address2    number 2        2024-10-06 00:00:00     2024-10-08 00:00:00
        100 address2    number 200      2024-10-08 00:00:00     null
--
        200 address1    park st         2024-10-06 00:00:00     null
        200 address2    number 20       2024-10-06 00:00:00     2024-10-08 00:00:00
        200 address2    number 200      2024-10-08 00:00:00     null                    */

请参阅此处的小提琴。