Item variations and differentiators

A product might have variants in terms of the size, color, and other attributes.

An enterprise might manufacture or sell items that are essentially the same but have some variation such as color and size. For example, a blue iPod and a red iPod are essentially the same product. To reduce the data entry and increase accuracy of the product information, the enterprise typically groups these items into one item family. This groupings allows reporting and analysis at the base item level. This concept is commonly referred to as item variations or differentiators.

The data model design for item variations depends on how much data can vary between the base item and the variant and client requirements around searching and assigning item identifiers.

Data modeling questions:

Item ID:: Does the base or variant item require an independent item identifier? For example, a SKU for iPod and a separate SKU for Blue iPod.
Search:: Should the base items or variants both be searchable?

Diff Val:: Can the variant have a different set of values, other than the distinguishing characteristics, compared to the base item? For example, can the variant have a separate description, supplier ID, and characteristics?

The following table illustrates the modeling options based on a set of key requirements.

Table 1. Key requirements of modeling item relationships
Modeling key points	Base items		Variants
	Item ID	Search	Item ID	Search	Diff val
Same catalog Separate items Relationship link between base and variant Variants cannot override base item attribute values	X	X	X	X
Same catalog Base item has multi-occurring attributes for depicting variants	X	X		X
Separate catalog Variants in item master catalog Relationship link between base and variant		X	X	X	X
Same catalog Separate items Relationship link between base and variant Variants can override base item attribute values	X	X	X	X	X