SQL and other tidbits provided by Marmot Library Network.
There are virtual items which are the product of resource sharing connection we have in Colorado. We use an Innovative program called INN-Reach to make it so that libraries that don't share a common database can still share items. Essentially it is a kind of Interlibrary loan system where the records don't live in your system until your patron requests one. Even then it is temporary. In order to place holds on these items patrons have to connect to the INN-Reach catalog and request from there. At that point the virtual item record is created. When the item returns to the lending library the virtual item disappears.
These SQL queries have been modified to pull the virtual item information.