[Django] #29049: Add slicing notation to F expressions
Django
-------------------------------------+-------------------------------------
Reporter: Matthew | Owner: nobody
Pava |
Type: New | Status: new
feature |
Component: Database | Version: master
layer (models, ORM) |
Severity: Normal | Keywords: slice F
Triage Stage: | Has patch: 0
Unreviewed |
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
-------------------------------------+-------------------------------------
For fields that are string expressions, the slicing notation should
utilize database functions `Substr`, `Left`, and `Right`. Those functions
could even be deprecated to require the use of slicing notation.
For fields that are iterable expressions, such as `ArrayField`s or
`HStoreField`s, those could utilize slicing notation in a Pythonic manner.
--
Ticket URL: <https://code.djangoproject.com/ticket/29049>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
Django
-------------------------------------+-------------------------------------
Type: New feature | Status: new
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: slice F | Triage Stage:
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Comment (by Tim Graham):
Could you give an example of what the syntax would look like?
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Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:1>
Django
-------------------------------------+-------------------------------------
Type: New feature | Status: new
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Comment (by Simon Charette):
I think this is a reference to [https://groups.google.com/d/msg/django-
developers/PsHDk1doTDg/B8iPrpgFAQAJ my post on the developers mailing
list].
That would be `F('textfield')[0:5]` which would map to `SubStr` and
`F('arrayfield')[0:10]` which would map to PostgreSQL `arrayfield[1:10]`.
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:2>
Django
-------------------------------------+-------------------------------------
Type: New feature | Status: new
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* stage: Unreviewed => Accepted
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:3>
Django
-------------------------------------+-------------------------------------
Type: New feature | Status: new
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* cc: Adam (Chainz) Johnson (added)
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:4>
Django
-------------------------------------+-------------------------------------
| Saxena
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: slice F | Triage Stage: Accepted
Needs tests: 1 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: nobody => Priyansh Saxena
* needs_docs: 0 => 1
* status: new => assigned
* needs_tests: 0 => 1
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:5>
Django
-------------------------------------+-------------------------------------
| Saxena
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: slice F | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* cc: josh.smeaton@… (added)
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:6>
Django
-------------------------------------+-------------------------------------
| Saxena
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 1
Needs tests: 1 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* has_patch: 0 => 1
Comment:
[https://github.com/django/django/pull/9670 PR]
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:7>
Django
-------------------------------------+-------------------------------------
| Saxena
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* needs_docs: 1 => 0
* needs_tests: 1 => 0
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:8>
Django
-------------------------------------+-------------------------------------
| Saxena
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* needs_better_patch: 0 => 1
Comment:
Comments on PR.
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Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:9>
Django
-------------------------------------+-------------------------------------
| Olofsson
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: Priyansh Saxena => Niclas Olofsson
Comment:
Taking over this since the current asignee hasn't worked on it in a while.
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:10>
Django
-------------------------------------+-------------------------------------
| Olofsson
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* needs_better_patch: 1 => 0
Comment:
New PR: https://github.com/django/django/pull/11208
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:11>
Django
-------------------------------------+-------------------------------------
| Olofsson
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 1 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* needs_better_patch: 0 => 1
* needs_tests: 0 => 1
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:12>
Django
-------------------------------------+-------------------------------------
| Olofsson
Type: New feature | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: slice F | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Needs tests: 1 | Patch needs improvement: 1
-------------------------------------+-------------------------------------
* cc: Sergey Fedoseev (added)
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:13>
Django
-------------------------------------+-------------------------------------
Type: New feature | Status: new
(models, ORM) |
Severity: Normal | Resolution:
Keywords: slice F | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Needs tests: 1 | Patch needs improvement: 1
-------------------------------------+-------------------------------------
* owner: Niclas Olofsson => (none)
* status: assigned => new
Comment:
Since feedback on the review came 10 months after I submitted the patch,
and it now has been more than a year since it was submitted, it would be
too much of an effort for me to put my mind into this again and get it
into a mergable state.
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:14>
Django
-------------------------------------+-------------------------------------
| Fedoseev
Type: New feature | Status: assigned
(models, ORM) |
Severity: Normal | Resolution:
Keywords: slice F | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Needs tests: 1 | Patch needs improvement: 1
-------------------------------------+-------------------------------------
* owner: (none) => Sergey Fedoseev
* status: new => assigned
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:15>
Django
-------------------------------------+-------------------------------------
| Smith
Type: New feature | Status: assigned
(models, ORM) |
Severity: Normal | Resolution:
Keywords: slice F | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Needs tests: 1 | Patch needs improvement: 1
-------------------------------------+-------------------------------------
* owner: Sergey Fedoseev => David Smith
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:16>
Django
-------------------------------------+-------------------------------------
| Smith
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Keywords: slice F | Triage Stage: Accepted
Has patch: 1 | Needs documentation: 0
Needs tests: 1 | Patch needs improvement: 1
-------------------------------------+-------------------------------------
* cc: Sergey Fedoseev (removed)
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:17>
Django
-------------------------------------+-------------------------------------
| Smith
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* needs_better_patch: 1 => 0
* needs_tests: 1 => 0
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:18>
Django
-------------------------------------+-------------------------------------
| Smith
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 1 | Patch needs improvement: 1
-------------------------------------+-------------------------------------
* needs_better_patch: 0 => 1
* needs_tests: 0 => 1
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:19>
Django
-------------------------------------+-------------------------------------
| Smith
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* needs_tests: 1 => 0
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:20>
Django
-------------------------------------+-------------------------------------
| Yadav
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: David Smith => Abhinav Yadav
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:21>
Django
-------------------------------------+-------------------------------------
| Yadav
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Comment (by Abhinav Yadav):
I have been reading up about this issue to continue and finish it off from
where David left it, and I have some doubts. The SQL query left by Felix
[https://github.com/django/django/pull/14731#discussion_r745505740 in this
comment] also doesn't generate any QuerySet or objects. I tried to run
that query using `Manager.raw()`, which generated no results.
Further I investigated the `resolve_expression` method of `SliceableF`
class in `django/db/models/expressions.py`, and compared it to other
implementations of resovle_expression method in other classes but couldn't
find anything concrete which might point to where the error might be.
Does a special method for handling slicing and indexing for OuterRef query
need to be written so it is properly resolved? That is what I'm thinking
because I can't find anything else that is properly handling slicing for
OuterRef Queries, unless I'm missing something.
Also should `None` be used instead of `''` in slice_expression for end if
length is not provided?
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:22>
Django
-------------------------------------+-------------------------------------
| Yadav
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* needs_better_patch: 1 => 0
Comment:
[https://github.com/django/django/pull/16310 PR]
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:23>
Django
-------------------------------------+-------------------------------------
| Yadav
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* needs_better_patch: 0 => 1
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:24>
Django
-------------------------------------+-------------------------------------
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: Abhinav Yadav => Nick Pope
* needs_better_patch: 1 => 0
Comment:
New [https://github.com/django/django/pull/17596 PR] with some fixes.
Hopefully we can finally get this over the line...
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:25>
Django
-------------------------------------+-------------------------------------
Reporter: Matthew Pava | Owner: Nick Pope
Type: New feature | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
| checkin
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* stage: Accepted => Ready for checkin
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:26>
Django
-------------------------------------+-------------------------------------
Reporter: Matthew Pava | Owner: Nick Pope
Component: Database layer | Version: dev
(models, ORM) |
Keywords: slice F | Triage Stage: Ready for
| checkin
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* status: assigned => closed
* resolution: => fixed
Comment:
In [changeset:"94b6f101f7dc363a8e71593570b17527dbb9f77f" 94b6f10]:
{{{
#!CommitTicketReference repository=""
revision="94b6f101f7dc363a8e71593570b17527dbb9f77f"
Fixed #29049 -- Added slicing notation to F expressions.
Co-authored-by: Priyansh Saxena <askpr...@gmail.com>
Co-authored-by: Niclas Olofsson <n...@niclasolofsson.se>
Co-authored-by: David Smith <smi...@gmail.com>
Co-authored-by: Mariusz Felisiak <felisiak...@gmail.com>
Co-authored-by: Abhinav Yadav <abhinav....@gmail.com>
}}}
--
Ticket URL: <https://code.djangoproject.com/ticket/29049#comment:27>