Google Cloud Spanner is a managed, distributed relational database from Google Cloud. Data is replicated using a synchronous, Paxos-based scheme, and according to Google Spanner offers global strong consistency and ACID transactions, so applications need no extra logic for eventual consistency. You can create databases using GoogleSQL or a PostgreSQL-compatible interface, which supports a subset of PostgreSQL. Spanner is delivered only as a managed cloud service and is proprietary software.
Google is a US company. Spanner offers regional, dual-region and multi-region configurations. In Europe, regional configurations exist in places such as Frankfurt, the Netherlands, Belgium, Warsaw and Paris; the multi-region configurations include eur3 (Belgium and the Netherlands, with Finland as witness) and eur7 (Milan and Frankfurt, with Turin as witness); and a dual-region configuration exists for Germany. Data can therefore be stored entirely within the EU, but the service remains in the hands of a US provider. For European organisations, legal control over the data therefore remains a point of attention alongside the choice of location.