如何从 BigQuery 中的 JSON 字符串中提取数组

Posted 2023-03-25

【中文标题】如何从 BigQuery 中的 JSON 字符串中提取数组

【英文标题】：How to extract array from JSON String in BigQuery

【发布时间】：2021-10-13 14:47:40

【问题描述】：

Hi, I'm working on a table looks like below:
----------------------------------------------------------------------------------------------------------------------------------------------
|     user_id    |                       j_games_information                                                   
----------------------------------------------------------------------------------------------------------------------------------------------
|   hsbdgcy76s   |"data": ["game_id": "acb", "rewards":["no":3,"items":"oils"],"game_id": "bsm", "rewards":["no":4,"items":"bombs"]]    
----------------------------------------------------------------------------------------------------------------------------------------------
|   kslcn6vg76   |"data": ["game_id": "ohf", "rewards":["no":6,"items":"oils"],"game_id": "dfg", "rewards":["no":7,"items":"bombs"]]   
----------------------------------------------------------------------------------------------------------------------------------------------

我的预期输出将是：

-----------------------------------
|     user_id    |     game_ids   |                                             
-----------------------------------
|   hsbdgcy76s   |      acb       |   
-----------------------------------
|   hsbdgcy76s   |      bsm       |   
-----------------------------------
|   kslcn6vg76   |      ohf       |   
-----------------------------------
|   kslcn6vg76   |      dfg       |   
-----------------------------------

我尝试了以下代码，但此查询未返回任何结果。谁能帮我这个？谢谢！

select user_id, JSON_EXRACT_SCALAR(json_array,"$.game_id") AS game_ids
from table, unnest(json_extract_array(j_games_information,"$.data")) AS json_array

但是

【参考方案1】：

尝试用j_games_information替换json_file

with mytable as (
    select 'hsbdgcy76s' as user_id, '"data": ["game_id": "acb", "rewards":["no":3,"items":"oils"],"game_id": "bsm", "rewards":["no":4,"items":"bombs"]]' as j_games_information union all 
    select 'kslcn6vg76' as user_id, '"data": ["game_id": "ohf", "rewards":["no":6,"items":"oils"],"game_id": "dfg", "rewards":["no":7,"items":"bombs"]]' as j_games_information
)
select user_id, JSON_EXTRACT_SCALAR(json_array,"$.game_id") AS game_ids
from mytable, unnest(json_extract_array(j_games_information,"$.data")) AS json_array

【讨论】：

Ops，我实际上使用了j_games_information。

嗯，你的查询对我有用