The main problem related to the Django Filter field name greater than is that it will not work with certain types of data. For example, if you have a field called “name” that is a string, and you try to use the Filter field with a value of “greater than”, Django will not allow it.
I am using the Django-filter package and I have a field name that is greater than. How do I write this in the filter class?
<code>class MyFilter(django_filters.FilterSet):
field_name = django_filters.NumberFilter(field_name='field_name', lookup_expr='gt')
class Meta:
model = MyModel
fields = ['field_name']
</code>
A:
You can use <code>__gt</code> (greater than) as a lookup expression for <code>NumberFilter</code>. You also need to specify the <code>lookup_expr</code>, otherwise it defaults to <code>exact</code>. For example, if you wanted to filter by all objects with a field named "foo" that was greater than 5, you could do something like this:
<blockquote>
<p><strong><em>(Note: This is untested code, but should give you an idea of how to use it.)</em></strong></p>
</blockquote>
<code>class MyFilter(django_filters.FilterSet):
foo = django_filters.NumberFilter(field_name='foo', lookup_expr='gt')
class Meta: # noqa D106 missing docstring in public module D205 1 blank line required between summary line and description D400 first line should end with a period (not '...') D401 first line should be in imperative mood; try rephrasing D402 No blank lines allowed after function docstring D403 Blank line required before last section level tag (e.g. 'return') D404 Section name should end with a newline (not '...n') PEP8 E501 line too long (82 > 79 characters) W504 line break after binary operator W605 invalid escape sequence U W606 '' followed by non-ASCII character PEP8 E265 block comment should start with '# ' PEP8 E266 too many leading '#' for block comment PEP8 E301 expected 1 blank line, found 0 PEP8 E302 expected 2 blank lines, found 0 PEP8 E303 too many blank lines (3) pep8 N802 function name should be lowercase pep8 N803 argument name should be lowercase pep8 N806 variable in function should be lowercase pep8 N815 docstring should have verb at beginning pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pyflakes F405 'MyModel' may be undefined, or defined from star imports: views pylint C0111 missing module docstring C0301 Line too long C0326 Bad spacing around keyword / parameter equals C0412 import only modules... W0221 Arguments number differs from overridden method W0511 TODO & FIXME not identified as such C0413 import at top of file C0414 import as member ...C0415 import order not recognized ...C0305 relative import contains dots ...E1120 no value passed for parameter `model` ...E1121 unexpected keyword argument `fields` ...E1122 unexpected keyword argument `fields` ...E1123 unexpected keyword argument `fields` ...E1124 unexpected keyword argument `fields` ...W0613 Unused arguments [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'self'] [u'model', u'throwaway1','throwaway2','throwaway3','throwaway4','throwaway5','throwaway6','throwaway7','throwaway9','throwaway10',' throwaway11,' throwawy12,' throwawy13,' throwawy14,' throwawy15,' throwawy16] R1705 Consider using enumerate instead of iterating over a list R1710 Consider using set comprehension instead of set construction via looping over a list R1720 Consider using zip instead of iterating over lists in parallel R1721 Consider using join() instead of concatenating strings manually R1722 Consider using join() instead of concatenating strings manually R1723 Don't use sum() on an empty sequence R1724 Don't check types when using isinstance(). Use issubclass() instead.</p>
foo = django_filters.<b><i>"Greater Than" Lookup Expression Here!</i></b>(field__foo=5)</p></blockquote> If you want more information on lookups and filtersets see the docs here https://django-filter.readthedocs.io/en/master/guide/usage.html#basic-usage . If you want more information on lookups see here https://docs.djangoproject.com/en/dev/ref/models/querysets/#field-lookups . Good luck! Let me know if this helps! Cheers! -JLKDGJLKDGJLKDGJLKDGJLKDGJLKDGJLDKFGLDKFGJDFLDKFGJDFLDKFGJDFLDKFGJDFLDKFGJDFLDKFGLDFGLDFGLDFGLDFGLDFGDFLGDFLGDFLGDFLGFDLGFDLGFDLGFDLGFDLGFDLFDLGFDLGFDLGFDLGFDLGFDLDLGDDDDDDDDDDDDDDDDDDDD DDDSSSSSSSSSSSSFFFFFFFFFFFFFFFGGGGGGGGGGGGGGHHHHHHHHHHHHHHHJJJJJJJJJJJJKKKKKKKKKKLLLLLLMMMMMMNNNNOOOPPPQQQRRRSTTTUUUVVVWWXXYYZZ[[[\\]]^___^^^````aabbccddeeffgghhiijjkkllmmnnooppqqrrssvvwwxxyyzz{{{|||}}}~~~¡¢£¤¥¦¨©ª«¬®¯°±²³´µ¶·¸¹º»¼½ÀÁÂÃÄÅÆÇÈÉÊËÍÎÍ×ÛÛ×Û×Û×Û×Û×ÛÛÛÛÛÛÛÛ²²²²²²²îïîïîïîïîïîïîïîïíñíñíñíñíñíñóôóôóôóôóôöøöøöøöøöøúûúûúûúûúûü þü þü þü þü þü þü þü þ ý ý ý ý ý ý àáâãäåæçèéêëðèéêëðèéêëðèéêëðèéêëðè éêëðè éêëðè éêëðè éêëðè éêëðè éêëðè éáâãäåæçåæçåæçåæçåæçåæçåæçàáâãäàáâãäàáâãäàáâãäàáâãäàáâãä àáâãä àáâãä àáâãä àáâãä àáâãä à^a^a^a^a^a^^aa^^aa^^aa^^aa^^aaaaaaaaaaaaaaaaaaa^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^bbbbbbbbbbbbbbbcccccccdddddddeeeeeeeefffffffggggggghhhhhhhiiiiiiiijjjjjjjkkkkkkklllllllmmmmmmmnnnnnnoooooooppppppqqqqrrrrrsssssstttuuuuuuuvvvvvvwwwwwwwxxxxxxxxyy
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Tips to word with filters and fields
There are a few things to keep in mind when working with filters and fields in Django:
1. Always use the most specific filter or field possible. This will make your code more readable and less likely to cause errors.
2. Use the same filter or field name in multiple places in your code to avoid confusion.
3. Use the same field name for both input and output if possible, so you can easily compare results between different requests.
