[ssharp]

I'm not sure about Census but Fivetran's free plan has met my needs to sync data from different ad platforms to BigQuery pretty well.

One of their pitfalls is charging by the row. If you're cost-conscious, you really need to watch what data you're syncing and you need to pare it down quite a bit during the 2-week period they give you when setting up a new connector. If you do all that though, you can get a lot of mileage out of the free plan for some use cases.

[tomrod]

Or batch massive rows? JSON structures in-database go a long way...