Checking if Two Massive Python Dictionaries are Equivalent

I have a massive python dictionary with over 90,000 entries. For reasons I won't get into, I need to store this dictionary in my database and then at a later point recompile dictionary from the database entries.

I am trying to set up a procedure to verify that my开发者_如何学JAVA storage and recompilation was faithful and that my new dictionary is equivalent to the old one. What is the best methodology for testing this.

There are minor differences and I want to figure out what they are.

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The most obvious approach is of course:

if oldDict != newDict:
  print "**Failure to rebuild, new dictionary is different from the old"

That ought to be the fastest possible, since it relies on Python's internals to do the comparison.

UPDATE: It seems you're not after "equal", but something weaker. I think you need to edit your question to make it clear what you consider "equivalent" to mean.

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You could start with something like this and tweak it to suit your needs

>>> bigd = dict([(x, random.randint(0, 1024)) for x in xrange(90000)])
>>> bigd2 = dict([(x, random.randint(0, 1024)) for x in xrange(90000)])
>>> dif = set(bigd.items()) - set(bigd2.items())

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>>> d1 = {'a':1,'b':2,'c':3}
>>> d2 = {'b':2,'x':2,'a':5}
>>> set(d1.iteritems()) - set(d2.iteritems()) # items in d1 not in d2
set([('a', 1), ('c', 3)])
>>> set(d2.iteritems()) - set(d1.iteritems()) # items in d2 not in d1
set([('x', 2), ('a', 5)])

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