Hi everyone, In our company, we also use the ability to define our own indexes, but with the current implementation of base Index class, we basically need to copy several methods entirely from it. What do we want is implement UNIQUE indexes with the UPPER function wrapper around field names [1]. This provides two benefits to us: 1) case-insensitive uniqueness of the field or the fields combination 2) quick filtering using iexact lookup, which uses UPPER(<field>) LIKE <string> statement in SQL (at least for the Postgres)
I think, adding more flexibility in current indexes build logic would help to implement and further support custom indexes implementations (like django-partial-index <https://github.com/mattiaslinnap/django-partial-index>) if we are not going to merge them in Django core or contrib. [1] https://gist.github.com/GeyseR/363b4b9d2d1cd8c91d51ebfe9369a7ac пт, 20 окт. 2017 г. в 14:37, Ashley Waite <ashley.c.wa...@gmail.com>: > I did a similar thing (but only tested in postgres) a while back, using > Q's / filter clause to generate the where clause. > > Perhaps with our powers combined we're close to a generalised > implementation? > > > https://github.com/ashleywaite/django-more/blob/master/django_more/indexes.py > > > > On Saturday, October 7, 2017 at 7:56:00 PM UTC+11, Mattias Linnap wrote: >> >> Hi django-developers, >> >> I have written a package that implements PostgreSQL and SQLite partial >> indexes on top of the new class-based indexes: >> https://github.com/mattiaslinnap/django-partial-index >> The most common use case is partial unique constraints, but I have a few >> projects where non-unique partial indexes have turned out useful as well. >> >> I have a few questions on how to continue with this: >> >> 1. Right now the "where condition" expression is provided as a string, >> and has to be different for PostgreSQL and SQLite in some common cases (for >> example boolean literals). Is there a good abstraction for SQL expressions >> somewhere in Django internals that I could use instead, something similar >> to Q-expressions perhaps? In particular, to add validate_unique() support >> to ModelForms, I would need to be able to extract all fields that are >> mentioned in the where condition. >> 2. I've seen mentions of a "check constraints" support being in >> development (https://github.com/django/django/pull/7615). Will that >> include partial unique constraints, or is just for the per-column checks? >> 3. If separate, then it would be nice to one day get partial indexes >> merged into the contrib.postgres package. Do you have any suggestions on >> what needs to happen before that - more test coverage, more contributors, >> more users, or similar? >> >> Best, >> >> Mattias >> > -- > You received this message because you are subscribed to the Google Groups > "Django developers (Contributions to Django itself)" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to django-developers+unsubscr...@googlegroups.com. > To post to this group, send email to django-developers@googlegroups.com. > Visit this group at https://groups.google.com/group/django-developers. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-developers/84f4431a-cdab-43c7-b96b-de4d2eb9805b%40googlegroups.com > <https://groups.google.com/d/msgid/django-developers/84f4431a-cdab-43c7-b96b-de4d2eb9805b%40googlegroups.com?utm_medium=email&utm_source=footer> > . > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Django developers (Contributions to Django itself)" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-developers+unsubscr...@googlegroups.com. To post to this group, send email to django-developers@googlegroups.com. Visit this group at https://groups.google.com/group/django-developers. To view this discussion on the web visit https://groups.google.com/d/msgid/django-developers/CAG-zk-CJnbuQASEmey6%2BWEewVrn8TPhxpUfv8TfzQEakAgwM%2Bw%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
