PDM-UG: Document source property
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This capability allows the specification of location of a document object in a digital or physical data storage system. This capability differs in its instantiation from the general document property pattern.
A central idea in capturing this requirement is that the document location comprises two components: storage node identification and path information. For digital files, for example, the storage item identification is equivalent to the file name, whereas the path information might describe the Internet node and directory in which the file can be found. The storage item identification is captured in applied_external_identification_assignment.assigned_id and the path information is mapped onto external_source.source_id.
The attribute identification_role.name is used to specify the mechanism being applied to identify the storage item and path information. Typical values for this attribute are ‘URL’ or ‘ISBN’ in the case of physical documents.
While applied_external_identification_assignment.assigned_id captures the file name, the attributes of the entity document_file allow for the specification of a unique identifier (attribute id) and nomenclature associated with the document or file (attribute name). The identifier is not necessarily the file name. However, if no document source property is assigned to a document_file, the following semantics may apply, depending on business process agreements:
- Document_file.id may specify the file name;
- In this case, document_file.id would suffice to unambiguously identify the document_file. In particular, it means that file names are defined in the context of a local directory.
The attribute identification_role.description specifies whether the location is associated with a source system, destination system or with some node form which the file or document can be retrieved. For example, the name of a given file used in a technical data package assembled for exchange purposes may differ from the name for the equivalent file in the source system.
Contents |
The Instance Model: EXPRESS entities and attributes
The instantiation diagram is shown below in Diagram 41.
Diagram 41: Document source property instance diagram
NOTE - Additional document properties can be defined on an individual basis.
Identification role
Identification role provides a name and a description for an identification assignment. In the context of this capability this entity specifies that the assignment structure be used to represent the document source property.
Attributes
- The name attribute characterizes the mechanism used to identify the storage item and the path information associated with the file or the representation of a document. Recommended values are:
- 'URL',
- 'FTP',
- 'ISBN' – for physical documents,
- 'Technical Data Package' – meaning that the location is associated with a technical data package being used for data exchange purposes,
- ‘tracking’ – for physical models.
- The description attribute identifies the context associated with the location of the file or document.
| ENTITY identification_role | Attribute Population | Remarks |
| name | type: label = STRING | |
| description | type: text = STRING | Must be 'source system', 'destination system' or 'access context' |
===Preprocessor Recommendations=== Identification_role.description shall be instantiated as 'source system', 'destination system' or 'access context' in the given context.
===Postprocessor Recommendations=== None specified.
===Related Entities=== None specified.
Applied external identification assignment
Applied_external_identification_assignment is used to assign an external source and identifier to a set of items.
Attributes
- The assigned_id attribute captures the storage node identification.
- The role attribute specifies the identification_role instance, which captures the location context and the mechanism used to express the location.
- The items attribute is a set of document representations or document files for which the document source information is valid.
| ENTITY applied_external_identification_assignment | Attribute Population | Remarks |
| assigned_id | type: label = STRING | |
| role | type: entity = IDENTIFICATION_ROLE | |
| items | type: set of entity = product_definition (for document representations) or document_file | document objects for which the document source property applies |
===Preprocessor Recommendations=== Applied_external_identification_assignment.assigned_id shall be instantiated with meaningful storage node location information of the file, document representation or physical module, even if this information is duplicated in the document_file attributes id or name.
===Postprocessor Recommendations=== None specified.
===Related Entities=== None specified.
External source
An external_source is the identification of a source of product related data. In the context of the document source property the external source provides the name of the source by which it can be accessed in a storage system.
Attributes
- The source_id attribute defines the path information associated with the file or document.
| ENTITY external_source | Attribute Population | Remarks |
| source_id | type source_item: STRING | specifies the path information |
| description | type text: STRING | DERIVED: Instantiation of this attribute is not required. |
===Preprocessor Recommendations=== None specified.
===Postprocessor Recommendations=== None specified.
===Related Entities=== None specified.
