GA Funnel Analysis in Big Query - "Correct" Session Counts - google-analytics

Question

Thank you for stopping by! I would be grateful to (re)create the ultimate GA Session Funnel in Big Query. The focus is on the funnel per session, with certain, but not necessarily sequentially visited pages during one session.
The solution should count sessions as COUNT( DISTINCT CONCAT(fullVisitorId, CAST(visitStartTime AS STRING))).
Further, the funnel should be of the form that every funnel step can only be reached if the previous step has been completed within a session (e.g. the fourth step should only be counted if steps 1 - 3 have been visited during the session). However, the steps do not need to be performed consecutively
That is, unfortunately, why this example, which I like a lot, would not work for me. It returns numbers for visits of totals.visits. Also, I need to use REGXP_CONTAINS for the pages, as I do not have events (or custom dimensions) on my pages for the funnel steps. For the original query (for every respective step)
SUM((SELECT 1 FROM UNNEST(hits) WHERE eventInfo.eventAction = 'landing_page' LIMIT 1)) Landing_Page
I tried:
COUNT( DISTINCT( SELECT CONCAT(fullVisitorId, CAST(visitStartTime AS STRING)) FROM UNNEST(GA.hits) WHERE REGEXP_CONTAINS(hits.page.pagePath, r”myfunnelpage”)
However, my funnel step visits are actually more than my total “sessions” as per COUNT( DISTINCT CONCAT(fullVisitorId, CAST(visitStartTime AS STRING))) AS overday_sessions.
Another example looks at user sessions (I am incredibly impressed, also absolutely intimidated, props to #Martin)
Allegedly, there is a website that ought to have it all is down when I wrote this #StuffGettingLostOnline
My approach would look something like this. But it returns only sessions with single page views, not sequential ones:
SELECT
date,
COUNT( DISTINCT( SELECT CONCAT(fullVisitorId, CAST(visitStartTime AS STRING)) FROM UNNEST(GA.hits) WHERE REGEXP_CONTAINS(hits.page.pagePath, r"productoverviewpage") LIMIT 1)) AS product_overview_s1,
COUNT( DISTINCT( SELECT CONCAT(fullVisitorId, CAST(visitStartTime AS STRING)) FROM UNNEST(GA.hits) WHERE EXISTS(SELECT 1 FROM UNNEST(GA.hitS) WHERE REGEXP_CONTAINS(hits.page.pagePath, r"productoverviewregex")) AND REGEXP_CONTAINS(hits.page.pagePath, cartoverviewregex") LIMIT 1)) AS cart_overview_s2
FROM
data as GA,
UNNEST(GA.hits) AS hits
WHERE hits.type = "PAGE"
AND
TRUE IN UNNEST(
[REGEXP_CONTAINS(hits.page.pagePath, r"productoverviewpage"),
REGEXP_CONTAINS(hits.page.pagePath, r"cartoverviewregex""]
)
Any ideas? Anyone able to recreate the ultimate big query funnel using the “correct” session count?

Answer 1

You can use inline subqueries to check for the individual steps of the funnel:
WITH
sessions AS (
SELECT
(
SELECT
hits
FROM
UNNEST(hits) hits
WHERE
hits.page.pagePath = "/"
) first_step,
(
SELECT
hits
FROM
UNNEST(hits) hits
WHERE
hits.page.pagePath = "/basket"
) second_step
FROM
`project.dataset.ga_sessions_*`)
SELECT
COUNT(first_step) sessions_step_one,
COUNTIF(first_step.hitNumber < second_step.hitNumber) sessions_step_two
FROM
sessions