Spanner is a distributed SQL database management and storage service developed by Google.
[1] It provides features such as global transactions, strongly consistent reads, and automatic multi-site replication and failover.
[4] Spanner's SQL capability was added in 2017 and documented in a SIGMOD 2017 paper.
[6] Spanner uses the Paxos algorithm as part of its operation to shard (partition) data across up to hundreds of servers.
[1] TrueTime is the brand name for Google's distributed cloud infrastructure, which provides Spanner with the ability to generate monotonically increasing timestamps in data centers around the world.