在 Google BigQuery 中查询 JSON 字符串

Posted 2023-03-24

【中文标题】在 Google BigQuery 中查询 JSON 字符串

【英文标题】：Query JSON string in Google BigQuery

【发布时间】：2021-03-13 21:50:57

【问题描述】：

我在 BigQuery 的一列中有以下 JSON 值，我正在努力将数据提取到列中。

我们的价值：

["availableSlots":0,"date":"03/16/2021","day":"Tue","slotType":"AM","totalSlots":5,"availableSlots":2,"date":"03/16/2021","day":"Tue","slotType":"PM","totalSlots":5,"availableSlots":5,"date":"03/17/2021","day":"Wed","slotType":"AM","totalSlots":5,"availableSlots":5,"date":"03/17/2021","day":"Wed","slotType":"PM","totalSlots":5,"availableSlots":5,"date":"03/18/2021","day":"Thu","slotType":"AM","totalSlots":5]

我正在尝试获取 availableSlots 的第一个和第二个值。

我确实尝试过 JSON_EXTRACT_SCALAR 和 JSON_EXTRACT

感谢您的帮助。

【参考方案1】：

见下例

with `project.dataset.table` as (
  select '["availableSlots":0,"date":"03/16/2021","day":"Tue","slotType":"AM","totalSlots":5,"availableSlots":2,"date":"03/16/2021","day":"Tue","slotType":"PM","totalSlots":5,"availableSlots":5,"date":"03/17/2021","day":"Wed","slotType":"AM","totalSlots":5,"availableSlots":5,"date":"03/17/2021","day":"Wed","slotType":"PM","totalSlots":5,"availableSlots":5,"date":"03/18/2021","day":"Thu","slotType":"AM","totalSlots":5]' col 
)
select 
  json_extract_scalar(json, '$.availableSlots') as availableSlots,
  json_extract_scalar(json, '$.date') as date,
  json_extract_scalar(json, '$.day') as day,
  json_extract_scalar(json, '$.slotType') as slotType,
  json_extract_scalar(json, '$.totalSlots') as totalSlots
from `project.dataset.table`, 
unnest(json_extract_array(col, '$')) json

有输出