schemas/VegCore/VegCore.ERD.mwb: tables with parent hierarchies: made parent optional, since the root(s) of the hierarchy will not have an entry for this, and any unique constraints that include this column should be ignored (which they will be if the value is NULL instead of a self-pointer)
schemas/VegCore/VegCore.ERD.mwb: tables with parent hierarchies: made parent optional, since the root(s) of the hierarchy will not have an entry for this, and any unique constraints that include this column should be ignored (which they will be if the value is NULL instead of a self-pointer)