将多行组合成单行，以 JSON object 为列

Question

我有一个表，我试图通过将所有 ID/部分组合组合成一行（总共有 3 个部分）嵌套 JSON 来减少数据集。表架构如下所示：

| ID       | Section  | Country  | Date   |
| -------- | -------- | -------- | ------ |
| 1        | 1        | US       | 1-1-11 |
| 1        | 2        | US       | 1-1-11 |
| 1        | 3        | US       | 1-1-11 |
| 1        | 1        | CA       | 1-1-11 |
| 1        | 2        | CA       | 1-1-11 |
| 1        | 3        | CA       | 2-2-22 |
| 1        | 1        | MX       | 2-2-22 |
| 1        | 2        | MX       | 2-2-22 |
| 1        | 3        | MX       | 2-2-22 |
| 2        | 1        | US       | 3-3-33 |

我想执行一个查询，将其转换为将 id/section 和国家/地区和日期组合成 JSON 字符串的东西

| ID/Section | Country/dates                      |
| ---------- | ---------------------------------- |
| "1,1"      | {"US;CA":”1-1-11;","MX":"2-2-22;"} |
| "1,2"      | {"US;CA":”1-1-11;","MX":"2-2-22;"} |
| "1,3"      | {"US":”1-1-11;","CA;MX":"2-2-22;"} |
| "2,1"      | {"US":”3-3-33;"}                   |

Answer 1

为此，您需要两个分组依据并连接所需的列。

首先，我们按 id、section、date 分组，之后仅按 id 和 section。

select id || ',' || section as id_section, '{'|| listagg(temp, ',') || '}' as country_dates
from (select id, section, '"' || listagg(country, ';') || '"' || ':' || '"' || date || '"' as temp
      from test.temp
      group by id, section, date) as t1
group by id, section;