jquery - 大查询SQL错误: Column name user_dim is ambiguous at [3:3]

Question

我如何运行一个查询来遍历我的 Android 和 iOS 数据以在一个表中返回我需要的内容。

当前，当我运行此命令时出现上述错误

#standardSQL
SELECT
  user_dim.app_info.app_instance_id,
  user_dim.device_info.device_category,
  user_dim.device_info.user_default_language,
  user_dim.device_info.platform_version,
  user_dim.device_info.device_model,
  user_dim.geo_info.country,
  user_dim.geo_info.city,
  user_dim.app_info.app_version, 
  user_dim.app_info.app_store,
  user_dim.app_info.app_platform
FROM

app.com_aaa_IOS.app_events_20171204，app.com_aaa_ANDROID.app_events_20171204

Answer 1

SELECT
  user_dim.app_info.app_instance_id,
  user_dim.device_info.device_category,
  user_dim.device_info.user_default_language,
  user_dim.device_info.platform_version,
  user_dim.device_info.device_model,
  user_dim.geo_info.country,
  user_dim.geo_info.city,
  user_dim.app_info.app_version, 
  user_dim.app_info.app_store,
  user_dim.app_info.app_platform
FROM
  app.com_aaa_IOS.app_events_20171204

UNION ALL

SELECT
  user_dim.app_info.app_instance_id,
  user_dim.device_info.device_category,
  user_dim.device_info.user_default_language,
  user_dim.device_info.platform_version,
  user_dim.device_info.device_model,
  user_dim.geo_info.country,
  user_dim.geo_info.city,
  user_dim.app_info.app_version, 
  user_dim.app_info.app_store,
  user_dim.app_info.app_platform
FROM
  app.com_aaa_ANDROID.app_events_20171204