创建老化报告查询

Question

我需要您的帮助，提出一个查询，该查询会给我付款时效报告。简单数据如下所示：

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| ID | Customer Name | Total Invoice | Paid Invoice | Paid Date | Amount | Aging 
---------------------------------------------------------------------------------
| 1  | David         |     $100      |     $0       |10/10/2018 |  $100  |  1    

| 2  | David         |     $100      |     $80      |15/10/2018 |  $20   |  5    

| 3  | David         |     $100      |     $100     |18/10/2018 |  $0    |  8    

| 4  | Jonh          |     $250      |     $0       |18/10/2018 |  $100  |  0    


---------------------------------------------------------------------------------
| ID | Customer Name | Total Invoice | Paid Invoice | Paid Date | Amount | Aging 
---------------------------------------------------------------------------------
| 1  | David         |     $100      |     $100     |18/10/2018 |  $0    |  8   

| 2  | Jonh          |     $250      |     $  0     |18/10/2018 |  $250  |  0    

Answer 1

您需要每个客户的最后一行。一种完善的方法是使用row_number Windows函数：

SELECT *
FROM   (SELECT *, ROW_NUMBER() OVER (PARTITION BY customer_name ORDER BY aging DESC) AS rn
        FROM   mytable) t
WHERE  rn = 1

Answer 2

尝试

SELECT *, LAST_VALUE(Aging) OVER (PARTITION BY customer_name ORDER BY aging DESC ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING)
FROM   mytable