BigQuery Export

BigQuery Export is GA4's built-in link that sends your raw, event-level analytics data into a Google BigQuery dataset you can query with SQL.

You turn it on in the Admin section under BigQuery Links, pick a project, and choose daily export, streaming, or both. From then on GA4 drops one row per event into date-partitioned tables. Nothing is pre-aggregated and nothing is sampled, so you get every parameter exactly as it was collected, ready to join against your own data.

Say your standard reports show a spike in purchases but the funnel looks off. In BigQuery you write a query against the events table, filter to the purchase event, and pull each session's full path plus the item parameters. You see the same user counted three times because a retry fired the event on reload, which the aggregated reports quietly folded together.

Free does not mean free to run. The export itself costs nothing for standard properties, but storing and querying that data in BigQuery bills under Google Cloud once you pass the free tier, and a careless full-table scan across months of events adds up fast.

It is the closest thing GA4 gives you to the raw truth.