Cosmos DB ¶

Azure Cosmos DB's API for PostgreSQL provides full support for SQL queries, geo-replication, and allows you to store and access data relationally. It offers automatic and instant scalability, global distribution, and effortless replication of data across Azure regions, fulfilling all of your mentioned requirements.
Apache Cassandra is a NoSQL database that does not natively support SQL queries. While it does offer some SQL-like capabilities, it is not a fully relational database.