SDB , an acronym for Simulation modelling DataBase is a Tcl extension by Tom Moore that provides a convenient and powerful language for defining simple models of dynamic systems.
SDB was designed as a language to facilitate the rapid description, prototyping, and implementation of the type of serial, sequential forecasting models that are popular in the field of forest resource management.
Although designed with natural resource management applications in mind, there may be other disciplines that can benefit from this modelling tool. When used with the TkTable widget, the SDB appears to operate much like a spreadsheet with automatic recomputation and display of interdependent variables.
Several examples are available online .