BigQuery 选择多个键值

Question

通过将 Firebase 中的自定义事件导出到 BigQuery，其中可以存在多个键值参数。我似乎无法弄清楚如何使用“标准 SQL”选择其中之一。

Answer 1

假设您要为所有事件选择string_value对应firebase_event_origin和int_value关联的。您可以将查询表示为：firebase_screen_idcontrol_reading

#standardSQL
SELECT
  (SELECT param.value.string_value
   FROM UNNEST(event_dim.params) AS param
   WHERE param.key = 'firebase_event_origin') AS firebase_event_origin,
  (SELECT param.value.int_value
   FROM UNNEST(event_dim.params) AS param
   WHERE param.key = 'firebase_screen_id') AS firebase_screen_id
FROM `your_dataset.your_table_*`
CROSS JOIN UNNEST(event_dim) AS event_dim
WHERE _TABLE_SUFFIX BETWEEN '20170501' AND '20170503' AND
  event_dim.name = 'control_reading';