db.query_database and other API list results returns a List object. The list object is an Enumerable object, so usually combines with .each method. Each Page or Block object is automatically mapped to a Ruby object when passed to a Ruby block.

Notion API returns only the first page-size objects. The default page-size of this library is 100. The page-size can be changed in Query object. Since the above .each method is supported for paging, it will automatically execute API call that obtain the following page-size objects when you used the first page-size objects. Users do not have to worry about paging.

db.query_database(query).each do |page|
  # exec some methods for a page object
end