But a query isn't run until I actually do something with the object, by loading it into memory by accessing or iterating over a queryset I'm performing potential time consuming operations. Isn't it better to do whatever work I can on the database? In some cases I could be doing something similar for thousands of records, surely this wouldn't be effective? Or am I simply overestimating the effort required for Python to work with the results?
On Thu, May 15, 2014 at 4:14 AM, Daniel Roseman <[email protected]>wrote: > On Wednesday, 14 May 2014 01:20:39 UTC+1, Anthony Hawkes wrote: >> >> Thanks for the answer! Do you think it would be practical to let the orm >> generate the base query and then doing a replace on the column name? I was >> thinking of this approach as a custom manager method to return a raw result. >> >> This would allow me the generate a case statement for the column and I >> could dynamically create it. >> >> Ant >> > You're thinking of this in the wrong way. Do you really need this data to > be generated by the database in the query? Once the original values are out > of the db and made into Python objects, you've got a whole powerful > object-orientated language available to you to do whatever transformations > you need on the data, ie Python. And you needn't do it at a queryset level: > each of the elements of the queryset is a model instance, and in the > process of accessing any of the values of those instances you're > necessarily interacting with the model object, so you can simply add > instance methods and call those instead of the original attributes. > -- > DR. > > -- > You received this message because you are subscribed to a topic in the > Google Groups "Django users" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/django-users/ZuSxc3YXA3c/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/django-users. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-users/fb2374d5-c928-4322-a0f0-517c24586eb6%40googlegroups.com<https://groups.google.com/d/msgid/django-users/fb2374d5-c928-4322-a0f0-517c24586eb6%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > For more options, visit https://groups.google.com/d/optout. > -- Anthony Hawkes E-Mail: [email protected] Ph: 0400 372 260 -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/django-users. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/CABqJoT0hL3U_Rt39x_wAMA%3Dtd68o8UrwkA2qJhZxT4%2BfNDDZPQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
