Logical and Graphic Existences of Model Elements
A model element exists precisely once in a model. A collection of all of a model element's data is referred to as a logical existence of this model element. However, a model element can be shown in any number of model views (diagrams, tables) (or in none at all). Model elements are displayed as graphic existences of the model element or as a reference to the logical existence of the model element.
Logical and Graphic Existences of a Model Element
A model element exists precisely once in a model. It can be identified by its UUID; its name, element type and path in the model hierarchy can also be used to identify it. All specifications that are available for the model element (UUID, name, path, texts, date of creation/change, user name of creator etc.) are always saved in the repository along with the model element. A collection of all of a model element's data is referred to as a logical existence of this model element.
However, a model element can essentially be shown in any number of model views (diagrams, tables) (or in none at all). Nevertheless, it always relates to the same model element: the same data always forms the basis, regardless of which display you are viewing the specifications in. This naturally also means that modifications to data which you make with an element's existence also affects all other existences. Model elements are displayed as graphic existences of the model element or as a reference to the logical existence of the model element.
Note
Graphic display is not mandatory. It can by all means be possible that a model element exists logically in an element but is not graphically displayed in a single diagram.
At first glance the statement that model elements can only be displayed once logically but as many times as required graphically may not appear to be anything special. However, some mechanisms are linked with this issue, which are perhaps not initially visible.
Creating vs. Adding
You need to take the difference between the logical and graphic instances of a model element into consideration in particular if you want to display a model element in a diagram or table: here you decide whether
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You want to create a model element that did not previously exist in the model or
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You want to display a model element in the current diagram that already exists in the model.
If you create an element in a diagram, you are establishing both its logical instance (its existence in the model) and its first graphic instance (in this diagram).
If you add an existing element to a diagram then you are creating a (or another) graphic occurrence of this element.
Deleting vs. Removing
As with creating or adding a model element, you also need to take logical or graphic existences into consideration if you no longer want to depict a model element in a diagram. Here you can decide whether
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The model element should be deleted from the entire model, including all its representations or
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Only one of its references should be removed from the diagram.
Adding and Displaying Relationships
So far we have only addressed which concept lies at the heart of adding model elements in a diagram. The question remains as to how this concept affects the relationships between model elements.
First: you will search for the Insert><Relationship> menu command to no avail. The carousel for the model element selected only shows the permissible selection of relationship types at first; once this has been selected, you can then select the relationship of the linked model element. This can be a model element which already exists and is displayed in the diagram or one which should be created as new.
You can control which relationships should be shown in a model view by showing and hiding them.
Copying – Creating and Inserting
You can copy some model elements and reinsert them into the desired new position again. At first, this function does not seem particularly complicated as you already know how to do it from other applications. However, in Innovator some fairly complex mechanisms are concealed behind the actual copying itself.
This basically applies:
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If you insert a copied model element into the table editor or model structure in a model itself, you create a new model element.
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If you insert a copied model element into a diagram in a model itself, you create a new model element and add a graphical existence of this model element in the diagram at the same time.
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A model element which has been copied in the model structure or diagram editor can only be inserted into a model structure or table editor.
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A model element which has been copied in the diagram can only be inserted into a diagram.
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