In python, sorting on date field, field may sometimes be null -


Coming to me in a real way to deal with this way. The data is back from reading the database I have. Although I want to sort on accoutingdate, sometimes it can be fake. I am currently working the following: 

  result = sorted (result, key = operator.atmeter ('accountingdate'), reverse = true)

But, because some details are empty, "this bomb with typeError: can not compare datetime.date for any type".

What is the "most accurate" or "most powerful" way to handle this? It's definitely okay to use the key = function, you have to decide how do you want to treat any values ​​- a Select Date Time Values ​​that you want to be considered equivalent to none for sorting purposes. Eg: 

  import routine brain = datetime.date (datetime.MINYEAR, 1, 1) def getaccountingdate (x): return x ['accountingdate'] or brain result = sort (result, key = Getaccountingdate, reverse = true)

Just see how simple it is by defining a cmp function - and if you do some benchmarking, then you It's also quite fast! There is no reverse in using the cmp function instead of the key function, and it would be a bad design to do this.


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