How do I do a not equal in Django queryset filtering?
In Django model QuerySets, I see that there is a __gt and __lt for comparitive values, but is there a __ne / != / <> ( not equals ?)
I want to filter out using a not equals:
Example:
Model:
bool a;
int x;
I want
results = Model.objects.exclude(a=true, x!=5)
The != is not correct syntax. I tried __ne , <> .
I ended up using:
results = Model.objects.exclude(a=true, x__lt=5).exclude(a=true, x__gt=5)
Maybe Q objects could be of help for this problem. I've never used them but it seems they can be negated and combined much like normal python expressions.
Update: I Just tried it out, it seems to work pretty well:
>>> from myapp.models import Entry
>>> from django.db.models import Q
>>> Entry.objects.filter(~Q(id = 3))
[<Entry: Entry object>, <Entry: Entry object>, <Entry: Entry object>, ...]
Your query appears to have a double negative, you want to exclude all rows where x is not 5, so in other words you want to include all rows where x IS 5. I believe this will do the trick.
results = Model.objects.filter(x=5).exclude(a=true)
To answer your specific question, there is no "not equal to" but that's probably because django has both "filter" and "exclude" methods available so you can always just switch the logic round to get the desired result.
the field=value syntax in queries is a shorthand for field__exact=value . That is to say that Django puts query operators on query fields in the identifiers. Django supports the following operators:
exact
iexact
contains
icontains
in
gt
gte
lt
lte
startswith
istartswith
endswith
iendswith
range
year
month
day
week_day
isnull
search
regex
iregex
I'm sure by combining these with the Q objects as Dave Vogt suggests and using filter() or exclude() as Jason Baker suggests you'll get exactly what you need for just about any possible query.
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