BigQuery - 为每一行连接字符串数组

Question

鉴于此输入：

Row     id      app_date    inventor   country
1       id_1    01-15-2022  Steve       US
                            Ashley      US
2       id_2    03-16-2011  Pete        US
                            Jamie       US
                            Mary        FR

我需要为每个 id 连接 inventor 个字符串，如下所示：

Row     id      app_date    inventors   
1       id_1    01-15-2022  Steve, Ashley
2       id_2    03-16-2011  Pete, Jamie, Mary

跟随 this example，我设法到达了这里：

Row     id      app_date    inventor
1       id_1    01-15-2022  Steve
                            Ashley
2       id_2    03-16-2011  Pete
                            Jamie
                            Mary

使用

WITH sample AS (
  SELECT "id_1" AS id, "01-15-2022" as app_date,
    [STRUCT("Steve" as name, "EN" as country),
     STRUCT("Ashley", "EN")]
       AS inventor
  UNION ALL SELECT "id_2", "03-16-2011",
    [STRUCT("Pete", "EN"), STRUCT("Jamie", "EN"), STRUCT("Mary", "FR")]),

    res as (
        SELECT id, app_date,
            (SELECT ARRAY(SELECT name FROM UNNEST(inventor))) AS inventors
            FROM sample
        )

SELECT id, app_date, inventors
FROM res

即该示例的倒数第二步。 inventors 列中的最后一步似乎是 ARRAY_TO_STRING，但我收到 No matching signature for function ARRAY_TO_STRING for argument types: ARRAY<STRING> 错误。

我在这里错过了什么？

Answer 1

考虑以下方法

SELECT * EXCEPT(inventor), 
  (SELECT STRING_AGG(name, ', ') FROM t.inventor) inventors
FROM sample t

如果应用于您问题中的示例数据 - 输出为

BigQuery - 为每一行连接字符串数组

BigQuery - concatenate array of strings for each row

sql

google-bigquery

unnest