1. A method of reorganizing a database and concurrently providing access to the database for updates, the database including an original data-space having a plurality of original data-elements and a shadow data-space having a plurality of shadow data-elements, the method comprising: copying contents of an original data-element within the original data-space to a shadow data-element within the shadow data-space; reorganizing the shadow data-space; keeping track of a location of an original data-element that is changed after its contents are copied to the shadow data-element; and copying data from the location of the changed original data-element to its corresponding shadow data-element in the reorganized shadow data-space.