How do I do a not equal in Django queryset filtering?

Question

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)

Answer 1

The last bit of code will exclude all objects where x!=5 and a is True. Try this:

results = Model.objects.filter(a=False, x=5)

Remember, the = sign in the above line is assigning False to the parameter a and the number 5 to the parameter x. It's not checking for equality. Thus, there isn't really any way to use the != symbol in a query call.

Answer 2

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>, ...]

Answer 3

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.