For a large e-commerce platform requiring operational databases during regional outages and capable of supporting millions of products with SQL compatibility, which GCP service is most suitable?

*Cloud Spanner with a multi-region configuration is the optimal choice for a large e-commerce platform that needs to ensure database operation during regional outages and support for millions of products, with a requirement for SQL compatibility. Cloud Spanner is a fully managed, scalable, and reliable database service that provides global distribution and strong consistency across regions, making it highly suitable for applications requiring robust disaster recovery capabilities. Its SQL compatibility ensures that it can seamlessly integrate with existing systems that use SQL. In contrast, services like Cloud Bigtable and Cloud Datastore, while scalable, do not offer SQL compatibility. Cloud SQL, despite being SQL-compatible, does not inherently provide the same level of global distribution and high availability as Cloud Spanner's multi-region configuration. Firebase Realtime Database is oriented towards real-time updates and is not primarily designed for SQL compatibility or handling the scale required for large e-commerce platforms.*