I want a nice design pattern for "All", "many" or "one"
Why would you want a single method to do three logically different things? Each method you make should really only perform one task. What's the problem in just having the consumer choose the method of selection based upon their need, instead of having a one method fits all sort of thing? If having three methods really isn't what you want, perhaps you could pass a Command pattern object to a database object, to execute the desired functionality?