Short for Redundant Arrays of Inexpensive Databases (Db), RAIDb is a standard for combining multiple database instances into an array of databases. RAIDb was derived from two technologies; Redundant Arrays of Inexpensive Disks (RAID) and computing clusters to provide better performance and fault tolerance than a single database would, with the benefits of a distributed workload, load balancing, and caching. RAIDb is defined at three different levels which vary the cost, performance and fault tolerances. The levels include the following:
- RAIDb-0: full partitioning
- RAIDb-1: full replication
- RAIDb-2: partial replication where the user defines the degree of replication of each database table.
Redundant Arrays of Inexpensive Databases was defined in September 2003 at INRIA (Institut National De Recherche En Informatique Et En Automatique) by Emmanuel Cecchet, Julie Marguerite, and Willy Zwaenepoel.