How are VoltDB partitions different from sharding a traditional database?
In sharding, the database tables are also partitioned. However, the partitions are actually separate, unrelated databases and it is the responsibility of the application code to manage the shards. More importantly, there is no guarantee of data or transactional consistency except whatever logic your application provides. With VoltDB, the database engine provides full ACID-compliance across the entire database and all partitions. Another cost of sharding is the complexity of managing the individual database instances. Backup, recovery, and all other management tasks must be performed separately for every node. With VoltDB, these management operations are coordinated centrally.
