I don't know yet Spot2 details.
The idea is just that some models can have a default ordering (I assume this functionality is present in Spot2 also).
And that some ORM may still add this ordering in the SQL query whilst it is not needed because only a single object will be prefetched per instance of the original result set.
On very big prefetches I noticed a gain of 10 - 15 %,
since the rest of the DB query is mainly an index scan.
ClimateChangeBrake
Can someone please dump the queries of such prefetches and see if the bug is present in Spot2 ?
If so submitting a PR should not be too hard.
I will try to help.
But right now, I start by warning the frameworks/ORM I am aware of :)
Hello,
Recently I found a problem with Django and submitted a patch in a PR: https://code.djangoproject.com/ticket/35309 https://github.com/django/django/pull/17984 I also developped a work-around for old versions of Django: https://github.com/LLyaudet/django-monkey-patches/blob/main/src/django_monkey_patches/django__orm__prefetch_without_useless_order_by.py
I don't know yet Spot2 details. The idea is just that some models can have a default ordering (I assume this functionality is present in Spot2 also). And that some ORM may still add this ordering in the SQL query whilst it is not needed because only a single object will be prefetched per instance of the original result set. On very big prefetches I noticed a gain of 10 - 15 %, since the rest of the DB query is mainly an index scan.
ClimateChangeBrake
Can someone please dump the queries of such prefetches and see if the bug is present in Spot2 ? If so submitting a PR should not be too hard. I will try to help. But right now, I start by warning the frameworks/ORM I am aware of :)
Best regards, Laurent Lyaudet