Big Query&GA4 source (not set) from GA4 not bringing any session results in Big Query

[ioana_p]

Hello!

When checking the sessions result in BQ vs GA4 for source, medium, and default channel grouping, the sessions for source = (not set) are not visible in BQ. Why is that happening? How can I correct it?

This is the formula I used to get session results by source, medium, and default_channel_grouping

SELECT

    CASE

        WHEN traffic_source.source IS NULL

             OR traffic_source.source = '' THEN '(not set)'

        ELSE traffic_source.source

    END as source,

    CASE

        WHEN traffic_source.medium IS NULL

             OR traffic_source.medium = '' THEN '(not set)'

        ELSE traffic_source.medium

    END as medium,

    CASE

        WHEN session_traffic_source_last_click.cross_channel_campaign.default_channel_group IS NULL

             OR session_traffic_source_last_click.cross_channel_campaign.default_channel_group = '' THEN '(not set)'

        ELSE session_traffic_source_last_click.cross_channel_campaign.default_channel_group

    END as default_channel_grouping,

    COUNT(*) as session_count

FROM `YOUR_PROJECT_ID].[YOUR_DATASET_ID].[YOUR_EVENT_TABLE_ID]`

WHERE event_name = 'session_start'

GROUP BY 1, 2, 3

ORDER BY session_count DESC;