SUB_CATEGORY

The DDL category sub_category provides data items to describe a subcategory and to associate a procedure with the subcategory. The procedure which is identified as _sub_category.method_id may be used to validate the subcategory. Subcategory validation may be required in instances where conditions are placed on the values of data items within the subcategory which are more restrictive than those associated with each component data item. A simple example of such a restriction would be a normalization restriction on the components of a subcategory. Any procedure referenced in this category must also be defined in category method_list (Section ). The method_list category also contains the parent definition for the item _sub_category.method_id. The definition of this item specified in this category serves to qualify the special role of the item in this child category.

The DDL for the sub_category category is given in the following section.

save_SUB_CATEGORY

    _category.description
;
     The purpose of a sub-category is to define an association between 
     data items within a category and optionally provide a method to 
     validate the collection of items.   The sub-category named 
     'cartesian' might be applied to the data items for the coordinates
      x,  y, and z.
;
    _category.id                         sub_category
    _category.mandatory_code             no 
    _category_key.name                 '_sub_category.id'
     loop_
    _category_group.id                 'ddl_group'
                                       'sub_category_group'
     save_


save__sub_category.id     

    _item_description.description
;
     The identity of the sub-category.
;
    _item_type.code                      idname             
     loop_
    _item.name                  
    _item.category_id                    
    _item.mandatory_code                  
         '_sub_category.id'                      sub_category           yes
         '_sub_category_examples.id'             sub_category_examples  yes
         '_sub_category_methods.sub_category_id' sub_category_methods   yes
         '_item_sub_category.id'                 item_sub_category      yes
     loop_
    _item_linked.child_name
    _item_linked.parent_name
         '_sub_category_examples.id'                  '_sub_category.id'
         '_sub_category_methods.sub_category_id'      '_sub_category.id'
         '_item_sub_category.id'                      '_sub_category.id'
     save_


save__sub_category.description

    _item_description.description
;
     Description of the sub-category.
;
    _item.name                         '_sub_category.description'
    _item.category_id                    sub_category       
    _item.mandatory_code                 yes 
    _item_type.code                      text
     save_