Current Version - Under Revision
If more than one snapshot view is required, the most effective approach is to implement a full view that enables a dynamic snapshot to be provided for any chosen time. The alternative approach is to create several separate snapshot views and to allow users to choose and where necessary switch between these static snapshots.
Each of these views in a multi- snapshot view is separately created and maintained in the same way as a single snapshot view . The required view for a particular purpose is selected from those available in the server. Where necessary more than one view may be selected to identify changes between versions.
In the long-term this approach requires more maintenance effort and more storage space than a full view and is far less flexible. It assumes a small set of discrete views such as those that arise from a relatively infrequent releases of SNOMED CT content. A more gradual evolution of content may occur in future as a result of the additions to Extensions and the ability to distribute delta releases . The multiple-snapshot approach may still meet the limited requirements of an organization needing access to two or three specified snapshot views (e.g. for current, previous and perhaps one other defined reference date). This approach may be useful as an interim measure in an environment that is unable to provide adequate performance for dynamic snapshot views .