fuel / orm

Fuel PHP Framework - Fuel v1.x ORM
http://fuelphp.com/docs/packages/orm/intro.html
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Does FuelPHP ORM suffer of the problem of useless order by on some ORM prefetches ? #453

Closed LLyaudet closed 6 months ago

LLyaudet commented 6 months ago

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 FuelPHP ORM details. The idea is just that some models can have a default ordering (I assume this functionality is present in FuelPHP ORM 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 FuelPHP ORM ? 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

WanWizard commented 6 months ago

The Fuel ORM doesn't do magic, it doesn't insert anything you haven't explicitly configured. There is no default ordering.

LLyaudet commented 6 months ago

Thanks for your answer :)