DSM, CDM, DRM, LDDM and DR-LDM Recreation A set of activities that includes producing a Data Scope Model (DSM), a Conceptual Data Model (CDM), a Data Requirements Model (DRM) a Logical Data Design Model and a Data Requirements – Logical Design Model (DR-LDM) that uses a top down approach to approximating a Rationalized Physical Data Model (RPDM). This is done as if the RPDM represented a user perspective instead of something that reflects what is already in production. In particular, the DRM may show some of the data requirements that the business consider no longer pertinent as obsolete, and other data requirements with some proposed changes in definition and/or formulation; the LDDM will offer a fully normalized design which will probably diverge from what is in the RPDM, especially in ignoring the data requirements that are considered obsolete.
This is a set of data modeling activities that contains the new ones that TDM proposes. The overall approach is TDM based. These activities set the stage and facilitate the final step of the reverse engineering into various data models.