Data Management Capabilities > Using Packages to Import and Export Data for Offline Collaboration > Import Received Delivery > Importing Incremental Received Delivery Files
  
Importing Incremental Received Delivery Files
If you have received more than one package delivery ZIP file from a source system, it is possible that the sender chose to send you an incremental delivery from what was previously delivered. The process to import incremental received delivery files is identical to the process to import full received delivery files. There are, however, two additional aspects to consider:
• Additional information contained in an incremental delivery
• The order in which received delivery files are imported
In some situations, you may receive a subsequent delivery from the same source system with updates to content that was previously delivered. You may receive a full delivery with all content that was previously delivered, or you may receive an incremental delivery with only information that has changed since the previous delivery. For example, if your company is collaborating with another company and you need to know about any modifications to their assembly, you could request regular updates to keep up with the modified data.
Unlike a full delivery, an incremental delivery is compared against a base delivery. This comparison allows an incremental delivery the unique opportunity to send information about objects that meet one of the following criteria:
• Deleted: Information about objects that have been removed from Windchill since the base delivery is sent so the same objects can be removed from the target system. During import, the system attempts to remove these same objects. Any objects that cannot be removed are reported.
• Absent: Information about objects that were sent in the base delivery but are no longer included in the current delivery because they were not included in the package. Possible reasons for exclusion may be that the collection options used to create the package have changed, the object may no longer meet the criteria, or the object was explicitly removed from the package. The preview and import reports on these objects as you may want to take further action on the objects, depending on your business process. For example, you can remove them from your system, move them to another context, or set a new life cycle state.
• Changed: Objects that have been modified in some way are sent. A change could be an update to a content file, modification to an attribute, moving the object to a new folder, and so on.
• New: Objects that are new in Windchill or are included in the package for the first time are sent.
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Incremental deliveries do not contain information about objects that are unchanged since the base delivery. Changed objects encompass both change initiated by the user and system level changes.
Incremental deliveries also carry the changed information about the association between a CAD document and a WTPart. Here is an exception when the change in association information is not shown clearly.
Consider a WTPart with image that is associated with a CAD document and is checked in to Windchill without build (Build Part After Associate preference or the Set for Single-Level Build option set to Off). If a package is made of these objects, when importing an incremental package after removing the association (See, Editing the Association of CAD Documents and Windchill Parts) to Windchill, the association removal between the WTPart and the CAD document is not clean.
As incremental deliveries are created on the source system by selecting a base delivery from which changes are assessed, there is often a dependency between the two deliveries. It is always a best practice to import the received delivery ZIP files in the same order as the files were exported, but it is more important for an incremental delivery. For more information, see Best Practices for Importing Received Delivery Objects.