A framework is provided that enables data mining algorithms to be plugged into it without any change to algorithm software implementations, while still providing all the standard data mining tasks. It may be implemented by the data source provider. It also then allows for the complete separation of data storage and algorithms. When the user initiates a mining session and picks an algorithm for build task or a model for an apply or test task, the framework may become responsible for preparing a set of "prompts" to the user asking him to provide some expression which is specific to the particular kind of data the user is working with.