Question

我想按国家/地区对下表进行分组，如果国家/地区为空，那么我想按州分组。有没有办法在纯SQL中做？如果状态没有条件，我可以分组！

+--------+-------+---------+
| EMP ID | STATE | COUNTRY |
+--------+-------+---------+
|      1 | AP    | IN      |
|      2 | UP    | IN      |
|      3 | MP    | IN      |
|      4 | NJ    | US      |
|      5 | NY    | US      |
|      6 | CA    | US      |
|      7 | PA    |         |
|      8 | PA    |         |
|      9 | CR    |         |
+--------+-------+---------+

预期输出：

+--------+-----------+---------+
| EMP ID |   STATE   | COUNTRY |
+--------+-----------+---------+
| 1,2,3  | AP,UP, MP | IN      |
| 4,5,6  | NJ,NY,CA  | US      |
| 7,8    | PA,PA     |         |
| 9      | CR        |         |
+--------+-----------+---------+

Answer 1

这样做：

WITH d AS (
SELECT 1 id, 'AP' state, 'IN' country FROM DUAL UNION ALL
SELECT 2 id, 'UP' state, 'IN' country FROM DUAL UNION ALL
SELECT 3 id, 'MP' state, 'IN' country FROM DUAL UNION ALL
SELECT 4 id, 'NJ' state, 'US' country FROM DUAL UNION ALL
SELECT 5 id, 'NY' state, 'US' country FROM DUAL UNION ALL
SELECT 6 id, 'CA' state, 'US' country FROM DUAL UNION ALL
SELECT 7 id, 'PA' state, null country FROM DUAL UNION ALL
SELECT 8 id, 'PA' state, null country FROM DUAL UNION ALL
SELECT 9 id, 'CR' state, null country FROM DUAL)
SELECT listagg(id,',') within group ( order by id),
       listagg(state,',') within group (order by state),
       country 
       FROM d
       group by nvl(country, state), country
       order by 1

Answer 2

在SELECT中使用case语句：

SELECT EMP_ID, STATE, CASE WHEN COUNTRY IS NULL THEN STATE ELSE COUNTRY END AS COUNTRY_STATE
FROM [TABLE]

然后您可以使用LISTAGG（）汇总值，具体取决于您的Oracle版本

SELECT LISTAGG(EMP_ID, ',') WITHIN GROUP,
    LISTAGG(STATE, ',') WITHIN GROUP,
    COUNTRY_STATE
FROM (
SELECT EMP_ID, STATE, CASE WHEN COUNTRY IS NULL THEN STATE ELSE COUNTRY        END AS COUNTRY_STATE
FROM [TABLE] )
GROUP BY COUNTRY_STATE

Oracle SQL中的条件分组

2 个答案: