It is possible to control whether an attribute can be modified or not. You can specify that certain attributes are Read-Only and others are Read/Write.
Grouping Attributes
Because the Bulkload utility adds the entire interface when it processes an attribute, an attribute that needs to be Read- Only should have its own interface, or it should be grouped into an interface with other Read-Only attributes.
The following picture shows one-to-one relationships between attributes and interfaces on an example CustomInterfaces sheet. There is one attribute per interface.
It is not recommended that every attribute in the catalog have its own interface
due to performance concerns. The recommended procedure is to group parameters logically,
so that an interface contains either all Read-Only attributes, or all Read/Write attributes.
Assigning Read-Only to Attributes
You can specify that an attribute is Read-Only by setting the flag on the CustomInterfaces sheet.
-
The attribute will be Read-Only for every part class in the workbook. If users will need to change the value of the attribute for one type of part but should not have access to the same attribute on another part, then this approach cannot be used.
-
The Read-Only flag is set on the part that is placed on the model, and it is also set on the attribute in the Catalog database.
Bulkloading Attributes
The following steps happen when the Bulkload utility adds attributes to a part class.
-
The interfaces are defined in the Catalog Schema. These interfaces come from the CustomInterfaces sheet that appears in each workbook.
-
A part class is added to the Catalog Schema.
-
The Bulkload utility processes the part class and adds it to the Catalog database, along with its attributes.
-
The Bulkload utility processes the attributes on the part class sheet. The Bulkload utility does the following:
-
Gets each attribute and looks for its interface on the CustomInterfaces sheet.
-
Adds the interface to the Catalog Schema and gives the attribute the appropriate (Read/Write or Read-Only) access.
-
Every attribute in an interface is given the same access.
Moving Attributes to New Interfaces
The following procedure moves attributes to new interfaces in the catalog. In this example, a group of attributes is split among two new interfaces.
-
Delete the interface on which the attributes had been placed. Locate the interface on the CustomInterfaces sheet, and type a D in the first column in that row. Run the Bulkload utility in the Add/Modify/Delete mode.
-
On the CustomInterfaces sheet, create new interfaces, and group the attributes.
-
To use the new interfaces, all part classes and items that use the attributes must now be modified. On a part class sheet, type an M in the first column of every row that uses the interfaces, including both the part class and item.
-
Run the Bulkload utility in the Add/Modify/Delete mode. This operation adds the interfaces from the CustomInterfaces sheet and modifies each part class and item to use the attributes from the new interfaces.
-
Synchronize the model and catalog to update all model occurrences to use the attributes form the new interfaces. For more information about synchronizing, see the Project Management User's Guide.
If the part class sheets use fully qualified interface names (example: Interface::UserAttribute<Symbol
Parameter>), you must edit the names on the part class sheets to reflect the new interfaces.
Remember that the same attribute name can be used in multiple interfaces as long as
a fully qualified name is used to define it for a part class.
Occurrence Attributes
Occurrence attributes are attributes with Read/Write access. These attributes are denoted by oa: at the top of a part class sheet.
In the software, occurrence attributes appear on the Properties dialog boxes, on the Occurrence tab or Parameters tab. If all oa: attributes are removed from the part class sheet, and the Bulkload utility is run, then all of the attributes will be Read-Only (grayed-out) on the Properties dialog boxes for parts in that part class.