Abstract: A database image may be updated with incremental changes without replicating the production database. Each set of changes to the production database are stored in a differencing disk. Two or more identical chains of differencing disks are created. One chain is an active chain, and database clones may be served from the active chain for use by users. After reaching a predetermined length on an inactive chain, the differencing disks on the inactive chain are merged into a single merged differencing disk, and the inactive chain becomes an active chain, from which new database clones may be served to users. The chains may alternate between being inactive and active chains.