(I don't think there's a direct analogue to Postgres though? Maybe people sometimes take data out of Spanner and put it in a Capacitor file instead sometimes?)
People dump data from the main OLTP to the "lake" or some OLAP database and call it data-warehouse vs. Internet-oriented companies like Google tend to focus more on querying the log and its aggregated data.
https://cloud.google.com/blog/products/bigquery/inside-capac...
(I don't think there's a direct analogue to Postgres though? Maybe people sometimes take data out of Spanner and put it in a Capacitor file instead sometimes?)