Checking if Two Massive Python Dictionaries are Equivalent

python dictionary transformation python-2.7
Spencer picture Spencer · Sep 30, 2011 · Viewed 18k times · Source

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 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.

Answer

unwind picture unwind · Sep 30, 2011

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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