Annotations are comments or short descriptions of actions performed on a file, such as merging or editing. For example, if a source file is merged into a target file, an annotation is written to the source file indicating the file into which the session of data was merged. This information may be retrieved by examining the source file’s merge output history, which is accessed by double- clicking the file name and selecting the Merge Output History tab from the Properties dialog. In addition, E-Merge writes an annotation to the target file indicating the source from which the data was merged. This information may be retrieved by examining the target file’s merge input history, which is accessed by double-clicking the file name and selecting the Merge Input History tab from the Properties dialog.
Annotations may be stored at the session level (as is the case with annotations relating to merge operations) or globally (as is the case with annotations relating to the renaming of variables). In most cases when a session is merged from a source file to a target file, the annotation is merged as well. When a source file contains global annotations, the global annotations are merged into the target file during the merge operation. In the target file, E-Merge appends the source file name in parentheses to the end of the global annotation being merged. This alerts the user that the global annotation originated in another file.
The exception to this involves annotations relating to merge operations. While an annotation for each merge operation is written to both the source file and the target file (as described above), annotations concerning previous merge operations are not carried from the source file to the target file during subsequent merge operations. The reason for this is that, in most cases, information concerning previous merge operations is relevant only to the source file, and therefore it is not necessary to record it in the target file.