Google analytics 在BigQuery上重新创建GA漏斗

我正在尝试使用BigQuery重新创建GA漏斗（Google 360上的自定义报告）。GA上的漏斗使用每个页面上发生的事件的唯一计数。我在网上发现这个查询在很大程度上是有效的：

SELECT
  COUNT( s0.firstHit) AS Landing_Page,
  COUNT( s1.firstHit) AS Model_Selection
from(
SELECT
      s0.fullvisitorID,
      s0.firstHit,
      s1.firstHit,
    FROM (
            # Begin Subquery #1 aka s0
            SELECT
                    fullvisitorID,
                    MIN(hits.hitNumber) AS firstHit
            FROm [64269470.ga_sessions_20170720]
            WHERE
                  hits.eventInfo.eventAction  in ('landing_page') 
                    AND totals.visits = 1
            GROUP BY
                  fullvisitorID
                  ) s0
    # End Subquery #1 aka s0

    left join (

    # Begin Subquery #2 aka s1
          SELECT
              fullvisitorID,
              MIN(hits.hitNumber) AS firstHit
          FROM [64269470.ga_sessions_20170720]
          WHERE
            hits.eventInfo.eventAction  in ('model_selection_page')
            AND totals.visits = 1
          GROUP BY
                fullvisitorID,
                ) s1

      ON
    s0.fullvisitorID = s1.fullvisitorID

    )

该查询工作正常，登录页的值与我在GA上得到的值相同，但Model_选择大约高出10%。这种差异在漏斗上也会增加（为了清晰起见，我只发布了两个步骤）。

---

你知道我在这里遗漏了什么吗

此查询满足您的需要，但版本为：

就这样。4条线路，更快更便宜

您还可以使用模拟数据，例如：

#standardSQL
WITH data AS(
  SELECT '1' AS fullvisitorid, ARRAY<STRUCT<eventInfo STRUCT<eventAction STRING > >> [STRUCT(STRUCT('landing_page' AS eventAction) AS eventInfo)] AS hits UNION ALL
  SELECT '1' AS fullvisitorid, ARRAY<STRUCT<eventInfo STRUCT<eventAction STRING > >> [STRUCT(STRUCT('landing_page' AS eventAction) AS eventInfo), STRUCT(STRUCT('landing_page' AS eventAction) AS eventInfo)] AS hits UNION ALL
  SELECT '1' AS fullvisitorid, ARRAY<STRUCT<eventInfo STRUCT<eventAction STRING > >> [STRUCT(STRUCT('landing_page' AS eventAction) AS eventInfo), STRUCT(STRUCT('model_selection_page' AS eventAction) AS eventInfo)] AS hits UNION ALL
  SELECT '1' AS fullvisitorid, ARRAY<STRUCT<eventInfo STRUCT<eventAction STRING > >> [STRUCT(STRUCT('model_selection_page' AS eventAction) AS eventInfo), STRUCT(STRUCT('model_selection_page' AS eventAction) AS eventInfo)] AS hits
)

SELECT 
  SUM((SELECT COUNTIF(eventInfo.eventAction = 'landing_page') FROM UNNEST(hits))) Landing_Page,
  SUM((SELECT COUNTIF(eventInfo.eventAction = 'model_selection_page') FROM UNNEST(hits) WHERE EXISTS(SELECT 1 FROM UNNEST(hits) WHERE eventInfo.eventAction = 'landing_page'))) Model_Selection  
FROM data

对于计数不同的用户，想法是相同的，但您必须应用

COUNT（distinct）

操作，如下所示：

SELECT 
  SUM((SELECT 1 FROM UNNEST(hits) WHERE eventInfo.eventAction = 'landing_page' LIMIT 1)) Landing_Page,
  SUM((SELECT 1 FROM UNNEST(hits) WHERE EXISTS(SELECT 1 FROM UNNEST(hits) WHERE eventInfo.eventAction = 'landing_page') AND eventInfo.eventAction = 'model_selection_page' LIMIT 1)) Model_Selection  
FROM data

SELECT 
  COUNT(DISTINCT(SELECT fullvisitorid FROM UNNEST(hits) WHERE eventInfo.eventAction = 'landing_page' LIMIT 1)) Landing_Page,
  COUNT(DISTINCT(SELECT fullvisitorid FROM UNNEST(hits) WHERE EXISTS(SELECT 1 FROM UNNEST(hits) WHERE eventInfo.eventAction = 'landing_page') AND eventInfo.eventAction = 'model_selection_page' LIMIT 1)) Model_Selection  
FROM data

---

嗨，威利安，谢谢你的回答。这是你一直在使用的一种有趣的方法。不过还是有一些简单的问题。我希望您使用这种结构区分用户和会话。看起来，在这种情况下，要计算的是总事件数。谢谢@Jacob谢谢你提出的另一个问题，我找到了你的评论，很抱歉花了这么长时间回答。我编辑了我的答案，希望这就是你想要的。让我知道它是否有效：）

SELECT 
  COUNT(DISTINCT(SELECT fullvisitorid FROM UNNEST(hits) WHERE eventInfo.eventAction = 'landing_page' LIMIT 1)) Landing_Page,
  COUNT(DISTINCT(SELECT fullvisitorid FROM UNNEST(hits) WHERE EXISTS(SELECT 1 FROM UNNEST(hits) WHERE eventInfo.eventAction = 'landing_page') AND eventInfo.eventAction = 'model_selection_page' LIMIT 1)) Model_Selection  
FROM data