[Django] #29771: Support database-specific syntax for bulk_update
Django
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Reporter: Tom | Owner: nobody
Forbes |
Type: | Status: new
Cleanup/optimization |
Component: Database | Version: master
layer (models, ORM) |
Severity: Normal | Keywords:
Triage Stage: | Has patch: 0
Unreviewed |
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
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As Simon points out here
(https://code.djangoproject.com/ticket/23646#comment:15) specialized
syntax can massively speed up `bulk_update()`.
Postgres supports using `UPDATE ... FROM`
([https://stackoverflow.com/questions/18797608/update-multiple-rows-in-
same-query-using-postgresql]) and we can possibly emulate this with MySQL
and `UNION ...`'s.
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Ticket URL: <https://code.djangoproject.com/ticket/29771>
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Django
-------------------------------------+-------------------------------------
Type: | Status: new
Cleanup/optimization |
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
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* stage: Unreviewed => Accepted
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Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:1>
Django
-------------------------------------+-------------------------------------
Type: | Status: new
Cleanup/optimization |
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
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Comment (by Vineeth Sagar):
Is anyone working on this? Can I have a go at it?
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Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:2>
Django
-------------------------------------+-------------------------------------
Type: | Forbes
Cleanup/optimization | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: nobody => Tom Forbes
* status: new => assigned
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Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:2>
Django
-------------------------------------+-------------------------------------
Type: | Forbes
Cleanup/optimization | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
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* cc: Tom Forbes (added)
Comment:
I think the groundwork to this is quite difficult to lay. The current
`SQLUpdateCompiler` is not suitable for this, I think.
Also I believe we can mimic this on SQLLite:
{{{
WITH test(id) AS (SELECT 1 UNION ALL SELECT 2)
UPDATE demo
SET name=(select id from test where id=demo.id)
WHERE id IN (select id from test)
}}}
Whether or not this is faster is something I'm not sure of. I believe the
MySQL syntax will be faster, and there is no SQL standard way of doing
this (I believe?), so we are left with a number of pretty different
workarounds. I'm not sure how to structure this nicely.
I can maybe hack Postgres support into the SQLUpdateCompiler, but it's
really not nice. We have to create all the aliases ourselves, manage the
different column names, etc etc.
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Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:3>
Django
-------------------------------------+-------------------------------------
Type: | Forbes
Cleanup/optimization | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
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* cc: Brillgen Developers (added)
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Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:4>
Django
-------------------------------------+-------------------------------------
Type: | Forbes
Cleanup/optimization | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* cc: Srinivas Reddy Thatiparthy (added)
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Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:5>
Django
-------------------------------------+-------------------------------------
Type: | Forbes
Cleanup/optimization | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
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/29771#comment:6>
Django
-------------------------------------+-------------------------------------
Type: | Forbes
Cleanup/optimization | Status: assigned
Component: Database layer | Version: master
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* cc: Shai Berger (added)
--
Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:7>
Django
-------------------------------------+-------------------------------------
Type: | Status: new
Cleanup/optimization |
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: Tom Forbes => (none)
* status: assigned => new
--
Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:8>
Django
-------------------------------------+-------------------------------------
Type: | Status: new
Cleanup/optimization |
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* cc: Akash Kumar Sen (added)
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Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:9>
Django
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Type: | Kumar Sen
Cleanup/optimization | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: (none) => Akash Kumar Sen
* status: new => assigned
--
Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:10>
Django
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Type: | Kumar Sen
Cleanup/optimization | Status: assigned
Component: Database layer | Version: dev
(models, ORM) |
Severity: Normal | Resolution:
Keywords: | Triage Stage: Accepted
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* cc: John Speno (added)
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Ticket URL: <https://code.djangoproject.com/ticket/29771#comment:11>