OpenQM

OpenQM, more commonly abbreviated to QM, is the only multi-value database available both as a fully supported commercial product and in open source form under the General Public License. QM is a combined development and runtime environment that allows construction of application software in a fraction of the time taken with some other widely used but significantly more expensive development toolsets. QM has a managed application environment in which user programs run, resulting in high reliability and ease of maintenance. Compiled applications are portable across all platforms (Windows, Linux, AIX, etc) unless operating system specific features are incorporated into the application by the developer. The environment is built around an integrated database package that uses the power and simplicity of the multi-value data model but can also support fully normalized relational data structures. The Virtual File System can be used to provide access to data in other data stores. QM applications are developed using a modern derivative of the Basic programming language, QMBasic, which is easy to learn and provides powerful data manipulation operations that can significantly increase developer productivity. Combined with the advantages offered by the multi-value data model, development times as low as one tenth of those for other methodologies have been reported. QM uses the multi-value or post-relational model in which the First Law of Normalization is discarded, allowing multiple values such as a list of products in an order to be stored together. The result is a data model that is more closely related to the real world and has the opportunity of giving significant performance improvements by keeping associated data together rather than being forced to separate it in order to comply with an apparently arbitrary rule.