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mongodb/how-to-query-a-random-row-using-pymongo
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mongodb/how-to-query-a-random-row-using-pymongo
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mongodb: How to query a random row using pymongo
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#. Get a count of every row.
#. Create an offset in the range of 1 to count.
#. Query for the item, skipping to the offset, limiting one result, and
   taking the [0]th index.

.. code-block:: python

::

   def getone( request ):
       id = request.matchdict[ 'id' ]
       if id == 'random':
           from random import randrange
           count  = request.db['people'].count()
           offset = randrange( 1, count )
           person = request.db['people'].find().skip( offset ).limit(1)[0]
       else:
           person = request.db['people'].find_one( { 'id': int(id) } )

       return { 'person': person }