Django查询不区分大小写的列表匹配

I have a list of names that I want to match case insensitive, is there a way to do it without using a loop like below?

我有一个要匹配不区分大小写的名称列表，有什么方法可以不使用下面这样的循环吗?

a = ['name1', 'name2', 'name3']
result = any([Name.objects.filter(name__iexact=name) for name in a])

6 个解决方案

#1

Unfortunatley, there are no __iin field lookup. But there is a iregex that might be useful, like so:

不幸的是，这里没有查找。但是有一个iregex可能是有用的，比如:

result = Name.objects.filter(name__iregex=r'(name1|name2|name3)')

or even:

甚至:

a = ['name1', 'name2', 'name3']
result = Name.objects.filter(name__iregex=r'(' + '|'.join(a) + ')')

Note that if a can contain characters that are special in a regex, you need to escape them properly.

请注意，如果a可以包含regex中特殊的字符，那么您需要正确地避开它们。

NEWS: In Djano 1.7 it is possible to create your own lookups, so you can actually use filter(name__iin=['name1', 'name2', 'name3']) after proper initialization. See https://docs.djangoproject.com/en/1.7/ref/models/lookups/ for details.

新闻:在Djano 1.7中，可以创建自己的查找，因此您可以在正确的初始化之后实际使用filter(name__iin=['name1'， 'name2'， 'name3'])。有关详细信息,请参阅https://docs.djangoproject.com/en/1.7/ref/models/lookups/。

#2

In Postgresql you could try creating a case insensitive index as described here:

在Postgresql中，您可以尝试创建一个不区分大小写的索引，如下所示:

https://*.com/a/4124225/110274

Then run a query:

然后运行一个查询:

from django.db.models import Q
name_filter = Q()
for name in names:
    name_filter |= Q(name__iexact=name)
result = Name.objects.filter(name_filter)

Index search will run faster than the regex matching query.

索引搜索将比regex匹配查询运行得更快。

#3

Adding onto what Rasmuj said, escape any user-input like so

再加上Rasmuj所说的，转义任何用户输入

import re
result = Name.objects.filter(name__iregex=r'(' + '|'.join([re.escape(n) for n in a]) + ')')

#4

Keep in mind that at least in MySQL you have to set utf8_bin collation in your tables to actually make them case sensitive. Otherwise they are case preserving but case insensitive. E.g.

请记住，至少在MySQL中，您必须在表中设置utf8_bin排序，以使它们区分大小写。否则它们保存大小写，但不区分大小写。如。

>>> models.Person.objects.filter(first__in=['John', 'Ringo'])
[<Person: John Lennon>, <Person: Ringo Starr>]
>>> models.Person.objects.filter(first__in=['joHn', 'RiNgO'])
[<Person: John Lennon>, <Person: Ringo Starr>]

So, if portability is not crucial and you use MySQL you may choose to ignore the issue altogether.

因此，如果可移植性不是很重要，而您使用MySQL，您可能会选择完全忽略这个问题。

#5

Another way to this using django query functions and annotation

使用django查询函数和注释实现此目的的另一种方法

from django.db.models.functions import Lower
Record.objects.annotate(name_lower=Lower('name')).filter(name_lower__in=['two', 'one']

#6

Here is an example of custom User model classmethod to filter users by email case-insensitive

下面是一个自定义用户模型类方法的示例，该方法通过邮件不区分大小写来过滤用户

from django.db.models import Q

@classmethod
def get_users_by_email_query(cls, emails):
    q = Q()
    for email in [email.strip() for email in emails]:
        q = q | Q(email__iexact=email)
    return cls.objects.filter(q)

#1