MicroKernel Database Engine, the transactional database engine, interacts directly with the data and does not require fixed data schema to access the data. It uses key-value store to store and access the data. Calls to the MKDE are made programmatically with Btrieve API rather than through the use of a query language; therefore, Zen does not have to parse the request. This places the MicroKernel Database Engine in the category of NotOnlySQL databases. Low-level API calls and memory caching of data reduce the time required to manipulate data.
