An in-memory database is a database system that uses the main memory of the computer or processing system for storage-rather than using a disk storage mechanism whips is done by normal Databases. It gives a definite advantage in terms of processing speed as the queries are executed faster when compared to a Disk Storage. In Memory databases are also called as main memory databases. They are mostly used in business scenarios where the data access time is quite crucial and needs to be optimized and lessened to the extent possible.
However, as the main memory is only a volatile storage area which loses its stored data when powered-off, in-memory databases have non-volatile storage options that allow data to be stored without loss. The first database to support both in-memory and disk storage (Called as a Hybrid Database) is WebDNA that was launched in 1995. Later on, the concept become quite popular in recent times and we have major Database Software Manufacturers offering their own versions of in-memory Databases.
1) SAP HANA (High Performance Analytic Appliance)
4) Informix Warehouse Accelerator
5) Microsoft SQL Server uses the Hekaton technology to build an in-memory database capability
6) TimesTen by Oracle
7) SQL CE by Microsoft
SAP HANA is a very popular choice of an in-memory database for enterprise needs and helps business solutions get the benefit of faster processing time-thus helping effective real-time execution. Its multi-lingual and is specially designed for business applications and for making way for faster business intelligence softwares.