What is the difference between Cloud SQL and Cloud Spanner?
1) Cloud SQL is a relational database service while Cloud Spanner is a globally distributed, horizontally scalable, and strongly consistent database service.
2) Cloud SQL is a NoSQL database service while Cloud Spanner is a relational database service.
3) Cloud SQL is a horizontally scalable database service while Cloud Spanner is a vertically scalable database service.
4) Cloud SQL is a managed database service while Cloud Spanner is a self-managed database service.
