GA4流量源数据与bigquery不匹配

Question

I have try to export traffic source data and event attribtion from bigquery and match with GA4 (session_source and session_medium) I am extract the event params (source ad medium) from bigquery but have a big gap between two data source

Any solution to solve it?

I have try to use use below SQL

with prep as (
select
    user_pseudo_id,
    (select value.int_value from unnest(event_params) where key = 'ga_session_id') as session_id,
    max((select value.string_value from unnest(event_params) where key = 'source')) as source,
    max((select value.string_value from unnest(event_params) where key = 'medium')) as medium,
    max((select value.string_value from unnest(event_params) where key = 'name')) as campaign,
    max((select value.string_value from unnest(event_params) where key = 'term')) as term,
    max((select value.string_value from unnest(event_params) where key = 'content')) as coXXntent,
    platform,
FROM `XXX` 
group by
    user_pseudo_id,
    session_id,
    platform
)

select
    -- session medium (dimension | the value of a medium associated with a session)
    platform,
    coalesce(source,'(none)') as source_session,
    coalesce(medium,'(none)') as medium_session,
    coalesce(campaign,'(none)') as campaign_session,
    coalesce(content,'(none)') as content,
    coalesce(term,'(none)') as term,
    count(distinct concat(user_pseudo_id,session_id)) as sessions
from
    prep
group by
    platform,
    source_session,
    medium_session,
    campaign_session,
    content,
    term
order by
    sessions desc

Answer 1

I'm also trying to figure out why BigQuery can't correctly match the source and medium to the event. The issue I found is that it assigns the source/medium as google/organic even though there is a gclid parameter in the link. The second issue is the huge deficiencies in recognizing the source as direct - in such cases I do not have these parameters for events at all.

The values are valid, but only for the source and medium that acquired the user.

As I compare data in UA and GA4 session attribution is correct. So it looks like a problem when exporting to BigQuery. I reported this to support and am waiting for a response.

Answer 2

I have also noticed source/medium does not align between BigQuery and GA4 and like Justyna has commented a lot of my source/medium come through as google/organic even when they are not. I am hoping Justyna will post here when there is a solution.

Looking at your code I can see 2 other areas that would cause discrepancies

1)

count(distinct concat(user_pseudo_id,session_id)) as sessions

This will only capture events with a valid pseudo_id and session_id, this is the correct way to count, but in my data there tends to be a few events without the ids are null so your session count included them but GA4 does.so use your preferred method of counting nulls to work out if this is an issue for you.

2): You are also doing an exact count which again is correct but GA4 does an approximant match see link below for details.

https://developers.google.com/analytics/blog/2022/hll#using_bigquery_hll_functions_with_google_analytics_event_data

Using the above two techniques I can get a lot closer to the GA4 number of session but they are still not attributed correctly