A Scoped Merged Union Catalog contains individual bibliographic records to which holding information for each item (location codes, barcodes, and so on) is linked. Each record must contain unique holding symbols (location codes) to identify each library. Each individual library site can use the scoping feature to browse only their local collection, selected collections, or all collections in the union catalog.

The system can link to the affiliated libraries using a WAN or the Internet. Transactions are updated instantaneously over the WAN. A T1 line is highly recommended for adequate performance during communications. This model runs on a central server solution.

Merged union catalogs can be updated centrally or locally.


M3 and Oasis allow any library system to be part of a virtual union catalog. Virtual Union Catalogs can easely be configured to operate on single or distributed server(s). For M3, a virtual union catalog is created by installing M3 Server and client software on one or multiple library automation servers, and M3 client software at each site. For Oasis, M3 Server and Oasis are installed on one or multiple library automation servers; no client software is needed. If desired, libraries can participate in a virtual union catalog but maintain their collections separately. Mandarin M3 and Oasis can search one, some or all library catalogs simultaneously. Transactions are updated instantaneously.