A new computer-readable medium, computer-implemented method, and system is provided which can allow a user to make changes to the planning data, generate a new plan, generate a new solution based on the generated plan, or perform an alternative scenario analysis on the generated plan. In one embodiment, a new model for representing planning data, identified as a “base-plus-delta” model is provided. In another embodiment, a new web service implementation for a planning engine is provided. In another embodiment, a new technique for copying plans to perform an alternative scenario analysis on the copied plan is provided. In another embodiment, an automatic propagation of user changes from a database directly to an in-memory object is provided. In certain embodiments of the invention, two or more of the described features can be combined to provide an interactive supply chain planning system.
