#28649: Add "week_year" lookup to DateField/DateTimeField
-------------------------------------+-------------------------------------
Reporter: Sigurd Ljødal | Owner: Sigurd
| Ljødal
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: ORM Extract | Triage Stage:
| Unreviewed
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Old description:
> I found myself in the need to extract the ISO year/week-numbering year
> (as specified by ISO 8601) from a date/datetime field, e.g. to group
> values by week. This is easy with PostgreSQL:
>
> {{{
> from django.db.models.functions import Extract, ExtractWeek
>
> SomeModel.objects.annotate(
> year=Extract('some_date', 'isoyear'),
> week=ExtractWeek('some_date'),
> ).values(
> 'year', 'week',
> ).annotate(
> sum=Sum('some_field'),
> )
> }}}
>
> but unfortunately this does not work across databases. I've implemented
> an `ExtractWeekYear` class with support for all databases and will submit
> a pull request shortly.
New description:
I found myself in the need to extract the ISO year/week-numbering year (as
specified by ISO 8601) from a date/datetime field, e.g. to group values by
week. This is easy with PostgreSQL:
{{{
from django.db.models.functions import Extract, ExtractWeek
SomeModel.objects.annotate(
year=Extract('some_date', 'isoyear'),
week=ExtractWeek('some_date'),
).values(
'year', 'week',
).annotate(
sum=Sum('some_field'),
)
}}}
but unfortunately extracting the week year like this does not work across
databases. I've implemented an `ExtractWeekYear` class with support for
all databases and will submit a pull request shortly.
--
Comment (by Sigurd Ljødal):
Hey felixxm, looks like you've misunderstood what I have implemented, it's
not the `ExtractWeek` class, but a cross database solution for
`Extract('some_date', 'isoyear')`. I've updated the description a bit to
clarify this.
The week-numbering year is different from the Julian year, as e.g. January
1st, 2017 is in week 52 of 2016.
--
Ticket URL: <https://code.djangoproject.com/ticket/28649#comment:4>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
--
You received this message because you are subscribed to the Google Groups
"Django updates" 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].
To view this discussion on the web visit
https://groups.google.com/d/msgid/django-updates/064.6fc6105cacdef288d4284b267967733d%40djangoproject.com.
For more options, visit https://groups.google.com/d/optout.
