在 SELECT SQL 中设置新字段优先级
Set new field priority in SELECT SQL
我有 table 个具有以下结构的帐单：
id | store_name | sum | payment_date
1 | Amazon | 10 | 11.05.2022
2 | Amazon | 20 | 11.05.2022
3 | Ebay | 15 | 11.05.2022
4 | AppleStore | 13 | 11.05.2022
5 | Google Play| 6 | 11.05.2022
我需要的是 select 来自 table 的所有数据，并根据账单金额设置附加字段“优先级”。前 2 行获得优先级 1，接下来的 2 行获得优先级 2，其他获得 0：
id | store_name | sum | payment_date | priority
2 | Amazon | 20 | 11.05.2022 | 1
3 | Ebay | 15 | 11.05.2022 | 1
4 | AppleStore | 13 | 11.05.2022 | 2
1 | Amazon | 10 | 11.05.2022 | 2
5 | Google Play| 6 | 11.05.2022 | 0
此外 table 包含不同日期的账单数据（字段 payment_date），应根据每一天的数据设置此优先级。
对每一天的行进行排序，然后根据行号分配优先级：
SELECT t.*,
CASE ROW_NUMBER()
OVER (PARTITION BY TRUNC(payment_date) ORDER BY sum DESC)
WHEN 1 THEN 1
WHEN 2 THEN 1
WHEN 3 THEN 2
WHEN 4 THEN 2
ELSE 0
END AS priority
FROM table_name t
其中，对于示例数据：
CREATE TABLE table_name (id, store_name, sum, payment_date) AS
SELECT 1, 'Amazon', 10, DATE '2022-05-11' FROM DUAL UNION ALL
SELECT 2, 'Amazon', 20, DATE '2022-05-11' FROM DUAL UNION ALL
SELECT 3, 'Ebay', 15, DATE '2022-05-11' FROM DUAL UNION ALL
SELECT 4, 'Apple Store', 13, DATE '2022-05-11' FROM DUAL UNION ALL
SELECT 5, 'Google Play', 6, DATE '2022-05-11' FROM DUAL;
输出：
ID
STORE_NAME
SUM
PAYMENT_DATE
PRIORITY
2
Amazon
20
2022-05-11 00:00:00
1
3
Ebay
15
2022-05-11 00:00:00
1
4
Apple Store
13
2022-05-11 00:00:00
2
1
Amazon
10
2022-05-11 00:00:00
2
5
Google Play
6
2022-05-11 00:00:00
0
db<>fiddle here
我有 table 个具有以下结构的帐单：
id | store_name | sum | payment_date
1 | Amazon | 10 | 11.05.2022
2 | Amazon | 20 | 11.05.2022
3 | Ebay | 15 | 11.05.2022
4 | AppleStore | 13 | 11.05.2022
5 | Google Play| 6 | 11.05.2022
我需要的是 select 来自 table 的所有数据，并根据账单金额设置附加字段“优先级”。前 2 行获得优先级 1，接下来的 2 行获得优先级 2，其他获得 0：
id | store_name | sum | payment_date | priority
2 | Amazon | 20 | 11.05.2022 | 1
3 | Ebay | 15 | 11.05.2022 | 1
4 | AppleStore | 13 | 11.05.2022 | 2
1 | Amazon | 10 | 11.05.2022 | 2
5 | Google Play| 6 | 11.05.2022 | 0
此外 table 包含不同日期的账单数据（字段 payment_date），应根据每一天的数据设置此优先级。
对每一天的行进行排序，然后根据行号分配优先级：
SELECT t.*,
CASE ROW_NUMBER()
OVER (PARTITION BY TRUNC(payment_date) ORDER BY sum DESC)
WHEN 1 THEN 1
WHEN 2 THEN 1
WHEN 3 THEN 2
WHEN 4 THEN 2
ELSE 0
END AS priority
FROM table_name t
其中，对于示例数据：
CREATE TABLE table_name (id, store_name, sum, payment_date) AS
SELECT 1, 'Amazon', 10, DATE '2022-05-11' FROM DUAL UNION ALL
SELECT 2, 'Amazon', 20, DATE '2022-05-11' FROM DUAL UNION ALL
SELECT 3, 'Ebay', 15, DATE '2022-05-11' FROM DUAL UNION ALL
SELECT 4, 'Apple Store', 13, DATE '2022-05-11' FROM DUAL UNION ALL
SELECT 5, 'Google Play', 6, DATE '2022-05-11' FROM DUAL;
输出：
ID STORE_NAME SUM PAYMENT_DATE PRIORITY 2 Amazon 20 2022-05-11 00:00:00 1 3 Ebay 15 2022-05-11 00:00:00 1 4 Apple Store 13 2022-05-11 00:00:00 2 1 Amazon 10 2022-05-11 00:00:00 2 5 Google Play 6 2022-05-11 00:00:00 0
db<>fiddle here