What happens when You Merge Projects

Project Merge requires a source project, a destination project, and a set of rules to resolve object conflicts between the two projects. This set of rules is defined in the Project Merge Wizard or loaded from an XML file.

In the Strategy system, every object has an ID (or GUID) and a version. (To see the ID and version of an object, right-click the object and select Properties.) Project Merge checks the destination project for the existence of every object in the source project, by ID. The resulting possibilities are described below:

• If an object ID does not exist in the destination project, the object is copied from the source project to the destination project.
• If an object exists in the destination project and has the same object ID and version in both projects, the objects are identical and a copy is not performed.
• If an object exists in the destination project and has the same object ID in both projects but a different version, there is a conflict that must be resolved. The conflict is resolved by following the set of rules specified in the Project Merge Wizard and stored in an XML file. The possible conflict resolutions are discussed in Resolve Conflicts when Merging Projects.

Merging projects with the Project Merge Wizard does not update the modification date of the project, as shown in the Project Configuration Editor. This is because, when copying objects between projects, only the objects themselves change. The definition of the project itself is not modified by Project Merge.