+1 On Thu, Sep 10, 2020, 11:35 AM Adam Johnson <m...@adamj.eu> wrote:
> What the purpose of having function that is not working correctly? >> > > You'll go further in life if you use more descriptive, less inflammatory > subjects. > > Also it's polite to search the ticket tracker for related issues before > posting on the list. This is the relevant ticket: > https://code.djangoproject.com/ticket/25705 > > Query.__str__ has never been intended as more than a debugging aid. Part > of the reason it's hard to compute the *actual* SQL is because Django > doesn't do it - it's done by the database library on cursor.execute(). This > is more than string quoting - some objects have special adapters, for > example JSON values. On top of this, there's no standard method in the > database libraries for SQL interpolation - it was never specified in DB API > ( https://www.python.org/dev/peps/pep-0249/ ). > > psycopg2 has a mogrify() function, but the other libarries don't - it may > require calling some internal/undocumented methods. Solving this ticket > needs some research and work. Your contributions would be welcome. > > On Thu, 10 Sep 2020 at 09:15, Alexander Lyabah <a.lya...@checkio.org> > wrote: > >> >> What the purpose of having function that is not working correctly, when >> you may not have this function at all and thing is changed. >> >> I'm talking here about function Query.__str__ >> >> Bellow I show you an example: >> >> In [19]: str(TimelineEvent.objects.filter(id__gt=100).query) >> Out[19]: 'SELECT "timeline_timelineevent"."id", >> "timeline_timelineevent"."created_on", >> "timeline_timelineevent"."modified_on", >> "timeline_timelineevent"."action_on", >> "timeline_timelineevent"."timeline_id", >> "timeline_timelineevent"."content_type_id", >> "timeline_timelineevent"."object_id", "timeline_timelineevent"."action", >> "timeline_timelineevent"."meta" FROM "timeline_timelineevent" WHERE >> "timeline_timelineevent"."id" > 100 ORDER BY >> "timeline_timelineevent"."action_on" DESC, "timeline_timelineevent"."id" >> DESC' >> >> In [20]: Timeline.objects.raw(str(TimelineEvent.objects.filter(id__gt=100 >> ).query)) >> Out[20]: <RawQuerySet: SELECT "timeline_timelineevent"."id", >> "timeline_timelineevent"."created_on", "timeline_timelineevent". >> "modified_on", "timeline_timelineevent"."action_on", >> "timeline_timelineevent"."timeline_id", "timeline_timelineevent". >> "content_type_id", "timeline_timelineevent"."object_id", >> "timeline_timelineevent"."action", "timeline_timelineevent"."meta" FROM >> "timeline_timelineevent" WHERE "timeline_timelineevent"."id" > 100 ORDER >> BY "timeline_timelineevent"."action_on" DESC, "timeline_timelineevent". >> "id" DESC> >> >> In [21]: len(Timeline.objects.raw(str(TimelineEvent.objects.filter(id__gt >> =100).query))) >> Out[21]: 89827 >> >> In [23]: str(TimelineEvent.objects.filter(id__gt=100, created_on__gt= >> datetime(2020, 1,1)).query) >> Out[23]: 'SELECT "timeline_timelineevent"."id", >> "timeline_timelineevent"."created_on", >> "timeline_timelineevent"."modified_on", >> "timeline_timelineevent"."action_on", >> "timeline_timelineevent"."timeline_id", >> "timeline_timelineevent"."content_type_id", >> "timeline_timelineevent"."object_id", "timeline_timelineevent"."action", >> "timeline_timelineevent"."meta" FROM "timeline_timelineevent" WHERE >> ("timeline_timelineevent"."created_on" > 2020-01-01 00:00:00+00:00 AND >> "timeline_timelineevent"."id" > 100) ORDER BY >> "timeline_timelineevent"."action_on" DESC, "timeline_timelineevent"."id" >> DESC' >> >> In [24]: len(Timeline.objects.raw(str(TimelineEvent.objects.filter(id__gt >> =100, created_on__gt=datetime(2020, 1, 1)).query))) >> ------------------------------------------------------------------------- >> -- >> ProgrammingError Traceback (most recent call last) >> /usr/local/lib/python3.5/dist-packages/django/db/backends/utils.py in >> _execute(self, sql, params, *ignored_wrapper_args) >> 83 else: >> ---> 84 return self.cursor.execute(sql, params) >> 85 >> >> ProgrammingError: syntax error at or near "00" >> LINE 1: ...timeline_timelineevent"."created_on" > 2020-01-01 >> 00:00:00+0... >> ^ >> >> And this function is recommended on stackoverflow all other the place. >> >> What would change if instead of >> >> def __str__(self): >> sql, params = self.sql_with_params() >> return sql % params >> >> We will have >> >> def __str__(self): >> return '{} | {}'.format(sql, params) >> >> In that case nobody will ever want to use it as argument for raw function. >> >> Thank you. And please, let me know what you think about it >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Django developers (Contributions to Django itself)" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to django-developers+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/django-developers/44595903-f679-4d08-abb8-80d2c8dec6e9n%40googlegroups.com >> <https://groups.google.com/d/msgid/django-developers/44595903-f679-4d08-abb8-80d2c8dec6e9n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > Adam > > -- > You received this message because you are subscribed to the Google Groups > "Django developers (Contributions to Django itself)" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to django-developers+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-developers/CAMyDDM3vjyUKPwJrKvmA5Rfp9-bZGykw8e6QrpWRCoNsg1BWnA%40mail.gmail.com > <https://groups.google.com/d/msgid/django-developers/CAMyDDM3vjyUKPwJrKvmA5Rfp9-bZGykw8e6QrpWRCoNsg1BWnA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Django developers (Contributions to Django itself)" group. 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