Docs: QuerySet slicing (SQL LIMIT)

[Thomas Güttler]

The current documentation for QuerySet slicing (SQL LIMIT) should be improved:

​https://docs.djangoproject.com/en/dev/topics/db/queries/#limiting-querysets

current:
For example, this returns the first 5 objects (LIMIT 5):
>>> Entry.objects.all()[:5]

add:
No Exception will be raised, if there are fewer results. 
If there are only four entries in the database table, the result will contain four entries.

[Aymeric Augustin]

QuerySets behave consistently with both SQL and Python:

$ sqlite3
sqlite> create table foo (id int);
sqlite> insert into foo (id) values (1);
sqlite> insert into foo (id) values (2);
sqlite> select * from foo limit 5;
1
2
sqlite> 

$ python
>>> range(4)[:5]
[0, 1, 2, 3]
>>> 

So the behavior of QuerySets is natural and expected.

In order to keep the docs straightforward, I think it's best to keep the text as is.

[Aymeric Augustin]

I asked on #django-dev, other developers agreed that the current doc is sufficient.