查询会话和命中级别的自定义维度

Question

索引为6 的customDimensions 对应于会话和命中级别的UUID。

在会话级别，我可以使用以下标准 SQL 查询来检索 UUID：

CREATE TEMP FUNCTION customDimensionByIndex(indx INT64, arr ARRAY<STRUCT<index INT64, value STRING>>) AS (
  (SELECT x.value FROM UNNEST(arr) x WHERE indx=x.index)
);

SELECT
customDimensionByIndex(6, customDimensions) AS session_uuid -- Customer UUID
FROM `94860076.ga_sessions_20170822`
limit 10

同样，在我可以使用的点击级别上：

CREATE TEMP FUNCTION customDimensionByIndex(indx INT64, arr ARRAY<STRUCT<index INT64, value STRING>>) AS (
  (SELECT x.value FROM UNNEST(arr) x WHERE indx=x.index)
);

SELECT
customDimensionByIndex(6, hits.customDimensions) AS hit_uuid -- Customer UUID
FROM `94860076.ga_sessions_20170822`, unnest(hits) as hits
limit 10

但是，我未能在同一个查询中同时使用两者。例如，我想要一个结果集，其中每一行对应一个会话，列是session_uuid 和array_of_hit_uuids。如何实现？

Answer 1

以下是 BigQuery 标准 SQL

#standardSQL
CREATE TEMP FUNCTION customDimensionByIndex(indx INT64, arr ARRAY<STRUCT<index INT64, value STRING>>) AS (
  (SELECT x.value FROM UNNEST(arr) x WHERE indx=x.index)
);
SELECT * 
FROM (
  SELECT
    customDimensionByIndex(6, customDimensions) AS session_uuid,
    ARRAY(
      SELECT val FROM (
        SELECT customDimensionByIndex(6, hits.customDimensions) AS val
        FROM UNNEST(hits) AS hits
      )
      WHERE NOT val IS NULL
    ) AS hit_uuid
  FROM `94860076.ga_sessions_20170822`
)
WHERE session_uuid IS NOT NULL
LIMIT 10

您可以使用公共数据集对其进行测试

#standardSQL
CREATE TEMP FUNCTION customDimensionByIndex(indx INT64, arr ARRAY<STRUCT<index INT64, value STRING>>) AS (
  (SELECT x.value FROM UNNEST(arr) x WHERE indx=x.index)
);
SELECT * 
FROM (
  SELECT
    customDimensionByIndex(2, customDimensions) AS session_uuid,
    ARRAY(
      SELECT val FROM (
        SELECT customDimensionByIndex(1, hits.customDimensions) AS val
        FROM UNNEST(hits) AS hits
      )
      WHERE NOT val IS NULL
    ) AS hit_uuid
  FROM `google.com:analytics-bigquery.LondonCycleHelmet.ga_sessions_20130910`
)
WHERE session_uuid IS NOT NULL
LIMIT 10