Create a database, populate it with a single document. Retrieve that document and change a property in it, then update it in the database.
Create a database, populate it with some documents having various structures, create a view based on a field common to all documents (the 'tags' field), and then query those documents using the view and print the results.
Demonstrate the use of (query-document). Create a database, populate it with some documents representing countries, use (query-document) to operate on this data.