Topic: BigQuery & Data Modelling Pillar article

BigQuery export for GA4 - the auditor view

Bernhard Prange · 2026-05-08 · 1 min read

Without the BigQuery export you hit a wall in GA4: no raw data, no custom SQL modelling, no retroactive audits. The auditor uses the export to reconcile sessions, conversions and e-commerce data against the live UI.

What is in the export

The GA4 BigQuery export delivers a daily events_YYYYMMDD table with all event records including user_properties, event_params and the associated device/geo struct.

Data-quality checks

  1. Event counts vs. GA4 UI: standard drift < 1 %.
  2. Conversions: every conversion must have a transaction_id.
  3. E-commerce: currency and value must never be missing.

Frequently asked questions

Do I need the BigQuery export for GA4?
Not for standard reports, but for serious audits: only the BigQuery export delivers event-level raw data for your own SQL modelling, retroactive analyses and checks that the GA4 UI does not show - duplicates, PII hints and funnel consistency.
Is the BigQuery export for GA4 free?
The GA4 export to BigQuery is free for standard properties. Only the usual BigQuery storage and query costs apply, which are low for typical audit queries.

bigquery ga4 data-quality

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