How to efficiently render calculated fields on a table?

[marcorichetta]

Thanks for answering Ken!

I tend to think that what I’m trying to do it’s already done by someone so, surely there’s a better way to do it than mine.

Here is the code from the models.

@KenWhitesell

My next thought would be to prefetch the values in the model methods and use the local variables in the calculations rather than trying to do the calculations at the database layer.

This is what I wanted to do from the beginning but I did it wrong and you corrected me.

Model property using another model field [Solved]

Right - the error is caused because you’re trying to use Variable as a module-level variable. Remove the module-level reference and the error goes away - no need at that point to comment lines. Briefly, yes. it would be perfectly valid to write: def real_price(self): return self.price * Variable.objects.get(pk=1).hour_price <opinion> (Side note: @property is syntactic sugar. In the context of Django, there are very few situations where it’s needed - and this isn’t one of them.) <opinion>…

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Possible solutions:

• I never implemented caching because this is a school project but I’d like to implement it if there’s the need.

• Another solution would be to refactor the functions to use Variable.objects... only one time. (What you’ve said above)

• Last but not least, I can exclude this fields from the table, avoiding the calculations in batch.