Offline Restructuring of DEDB Databases

An IMS DEDB database restructure operation creates an empty offline DEDB having the desired structure. The offline database is populated with data from a source (online) database while keeping the source database online (i.e., available for access and update operations). Updates to the source database made during this process are selectively processed in parallel with the offline DEDB load operation. When the contents of the offline database is substantially the same as the source or online database, the source database is taken offline, final updates to the offline database are applied whereafter the offline database is brought online, thereby replacing the source database. It is significant to note that updates occurring to the source or online DEDB are applied to the offline DEDB.