Often all the locations in a data area have the same scope in the source program. 一個數據區中所有單位在源程序中常常有相同的定義域。
A backup that contains only the data extents that were modified since the most recent partial backup of the same set of filegroups. 這種備份僅包含自同一組文件組的最新部分備份以來發生了修改的數據區。