I apologize for such a late reply. I am new to mail groups and all. Thank you very much for pointing this out. Guess it's easy to forget querysets are lazy ;)
On Saturday, 16 February 2019 00:49:19 UTC+5:30, Simon Charette wrote: > > I meant, and *not* "Building a queryset" in my previous reply. > > Le vendredi 15 février 2019 14:18:27 UTC-5, Simon Charette a écrit : >> >> Hello Philoj, >> >> > Does this mean that the above code example will raise >> TransactionManagementError... >> >> It won't cause a TransactionManagementError because of the lazy nature of >> queryset. >> >> Even if the QuerySet.select_for_update() call is made outside of the >> atomic block the query >> is really only executed when entries are iterated over. >> >> Given the documentation clearly mentions "*Evaluating* a queryset" and >> "Building a queryset" >> I don't think it's worth amending it. >> >> Cheers, >> Simon >> >> Le vendredi 15 février 2019 07:40:51 UTC-5, Philoj Johny a écrit : >>> >>> In the documentation for select_for_update >>> <https://docs.djangoproject.com/en/2.1/ref/models/querysets/#select-for-update>, >>> >>> given code example is: >>> >>> from django.db import transaction >>> entries = Entry.objects.select_for_update().filter(author=request.user)with >>> transaction.atomic(): >>> for entry in entries: >>> ... >>> >>> At the same time, below in the description it says that: >>> >>> *Evaluating a queryset with select_for_update() in autocommit mode on >>> backends which support SELECT ... FOR UPDATE is a >>> TransactionManagementError >>> <https://docs.djangoproject.com/en/2.1/ref/exceptions/#django.db.transaction.TransactionManagementError> >>> error because the >>> rows are not locked in that case.* >>> >>> *Does this mean that the above code example will raise >>> **TransactionManagementError , since the select_for_update_query is >>> evaluated outside atomic block?* >>> >>> >>> *(I have'nt actually tried this out yet, will soon. I think may be a >>> correction is required in the code example)* >>> >>> -- 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 https://groups.google.com/group/django-users. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/f0f584df-f9a5-42a9-a798-9f712ee1d07f%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
