Why is it required to define a MIME Type for a content provider, What does a MIME Type Signify?? I Know that for a single item you define Item and for directory you say Dir.Suppose you are creating a database for Library how do you define a MIME Type for it and Why?? Can you please explain this??
A MIME type is to a browser what a file extension is to Windows - it is a way of identifying the contents of the file and optionally allowing an executable to be assigned to the file (where the executable understands the file contents). For more details: http://en.wikipedia.org/wiki/Internet_media_type
But the rest of your question confuses me - where did you read that you need a MIME type for a "database for Library". And what do you mean by "Library"? There is no class by that name...