US Patent 8429162 Facilitating data redistribution in database sharding

Disclosed are various embodiments for facilitating data redistribution in database sharding. A database is maintained that is horizontally partitioned into a set of first buckets using modulo-based assignments. A fixed number of the first buckets are stored in each of multiple physical data stores. The database is repartitioned into a set of second buckets using modulo-based assignments. The number of second buckets in the set is a multiple of the sum of a positive integer and the quantity of the physical data stores. The data in the database is unmoved between the physical data stores by repartitioning.