Data Measured

19 Jul 2024 · GA4 · medium severity · fix verified 9 Sept 2026

Session traffic source record in the GA4 BigQuery event export

'We've added a new record to the GA4 BigQuery Event export that contains the Google Ads and Manual campaign context information for each session present in the export.'

Source: What's new archive — Jul 19, 2024.

What it breaks

Hand-built session attribution in BigQuery is now the second-best source; older queries disagree with the interface.

Who it hits: BigQuery users.

The fix

Read session source from the new record.

fix artifact · #A-004

GA4 BigQuery: sessions with last-click source and key events

One query over the events_* export: sessions per day, the session's last-click source from the record Google added in July 2024, and key events per session.

verified_on
2026-09-09
next re-check
2026-12-01
status
current

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