Attributes that can be multi-valued shall be in their own tables, along with any other attributes that are functionally dependent. For example, say entity "road" has attributes "num_lanes", "name", "oper_status", and "route_number." "Name" can have many values for a single entity instance. Further, every value of "name" may have its own route number. Since the value of attribute "route_number" is dependent on "name" then both of these are put in their own table. The modules that follow illustrate the proper way to handle multi-valued attributes.
The line module LE01 references the attribute records in the Attribute Primary modules that describe the entity instance being represented. The attribute module AP12 contains the attributes that are not multi-valued for entity "road". The attribute module AP13 contains the multi-valued attribute "name" along with its functionally dependent attribute "route_number".
Repeating the row, as shown in the following modules, is an undesirable solution. Attributes that do not repeat are duplicated in subsequent rows. It is not clear whether the two attributes with changing values are related or not.
NOT the proper way of handling multi-valued attributes.