The creation of the BOM structure of an item for an order is called Derivation. The derivation takes account of all special requirements, variants and optional items.
The variant form is a table that belongs to the variant wildcard. This table contains all items, which are then used for order creation (derivation) to replace the variant wildcard by means of a manual or automatic selection (decision table).
In addition, the specific characteristics defined by the variant wildcard are specified in the variant form.
All items that are to be displayed in the variant form must have been defined in Item management. However, they may also contain a structure.
Identical items are items located below the variant wildcard. These items or components are refered to as "identical items", because they are always required regardless of the item variant. For example, ball pen refills of different color are used for a certain ball pen. In this case a nib would always be used as identical item.
Optional BOM items are special types of variant wildcards. They represent item wildcards which use a 'Be or not to be' approach. They always represent either a certain item or no item at all. For example, the ornamental ring of a ball pen could be such an optional part. A simple ball pen does not necessarily have such an ornamental ring, while a higher-quality pen surely has one.
If a part is an optional part can be seen by the 'o' for optional in the T column of the structure BOM. If the column contains 'm', this part is a required part.
Parameterized BOM items are special types of variant wildcards. They may vary in characteristics not relevant for the structure of the bill of material. A company plans to send their customers e.g. a ball pen. The company wishes an additional print label on the upper ball pen part as a special feature. Now the type of the ball pen upper part remains unchanged and it is contained in the bill of material, but in this case it bears a special print label. Therefore it is created as parameterized BOM item. This parameterized BOM can only be derived from a decision table (system variable ART_PAR).