I have a rule – any conversion or upgrade will require the creation of a decommission plan. A decommission plan should include the following: A list and definition of each database, table and column (source and target). A list and definition of each of the current programs in use (you

The physical data model should represent exactly the way the tables and columns are designed in the in the database management system.  I recommend keeping storage, partitioning, indexing and other physical characteristics in the data model if at all possible.  This will make upkeep and comparison with the development, test