NOSQL vs XML document storage

When to choose NoSQL and when 开发者_如何学Pythonto choose XML ?

Update: I want to know when one can use NoSQL exclusively, XML exclusively or both. I want real examples not generalities.

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I want to get some goods from my shop to a customer. Do I walk, or should I use a SatNav?

Your question seems rather confused. NoSQL and XML aren't obviously clear alternatives - you could store your documents using XML in a NoSQL type database. Please clarify what you already have, what you want to do and what your constraints are.