Oracle BI repository has three types of merges.
Full merges, sometimes called upgrade merges, are used during development processes, when there are two different repositories that need to be merged. The Administration Tool provides a three-way merge feature that lets you merge two repositories that have both been derived from a third, original repository. Full merges can also be used to import objects from one repository into another, see Performing Full Repository Merges.
Patch merges are used when you are applying the differential between two versions of the same repository. For example, you might want to use a patch merge to apply changes from the development version of a repository to your production repository, or to upgrade your Oracle BI Applications repository, see Performing Patch Merges.
Multiuser development merges are used when you are publishing changes to projects using a multiuser development environment, see About the Multiuser Development Merge Process.
The merge process typically involves three versions of an Oracle Business Intelligence repository: the original repository, modified repository, and current repository. The original repository is the original unmodified file, the parent repository, while the modified and current repository are the two changed files you want to merge. The current repository is the one currently open in the Administration Tool.
The original, modified, and current repository may mean different things, depending on your situation. For example:
In a development-to-production scenario, you have an original parent file, a current file that contains the latest development changes, and a modified file that is the deployed copy of the original file.
In an Oracle BI Applications repository upgrade scenario, the current file is the latest version of the repository shipped by Oracle, and the original file is the original repository shipped by Oracle. The modified file is the file that contains the changes you made to the original file.
You can use patch merge with both of these situations. In a patch merge, you open the current file and select the original file, then generate the patch. To apply the patch, you open the modified file and select the original file, then apply the patch.