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Django Queryset

Subject : it-skills

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. This query finds all entries between a start date of start_date and an end date of end_date.
Entry.objects.filter(pub_date__range=(start_date - end_date))
relationship spanning
help_text
gte

2. Returns a dictionary of aggregate values (averages - sums - etc) calculated over the QuerySet. Each argument to this method specifies a value that will be included in the dictionary that is returned.
many-to-many relationship
Manager methods
aggregate(args - *kwargs)
distinct()

3. This model method saves a model instance to the database. This method has no return value.
ForeignKey
save()
one-to-one relationship
|

4. If True - the table does not permit duplicate values for this field.
month
unique
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
defer(*fields)

5. Lookup type that finds a case-sensitive regular expression match.
|
regex
values(*fields)
lt

6. Returns a new QuerySet that uses SELECT DISTINCT in its SQL query. This eliminates duplicate rows from the query results.
distinct()
Entry.objects.filter(id__gt=4)
intermediate models
Abstract base class

7. Lookup type that returns results greater than a given value.
Manager
defer(*fields)
order_by(*fields)
gt

8. Adds to each object in the QuerySet with the provided list of aggregate values (averages - sums - etc) that have been computed over the objects that are related to the objects in the QuerySet. Each argument to this is content that will be added to ea
create(**kwargs)
annotate(args - *kwargs)
gt
none()

9. This tells Django how to calculate the URL for an object. Django uses this in its admin interface - and any time it needs to figure out a URL for an object.
many-to-one relationship
defer(*fields)
get_absolute_url()
using(alias)

10. Lookup type that returns results with a case-insensitive start sequence.
istartswith
one-to-one relationship
filter(**kwargs)
primary_key

11. Negation operator for Q objects.
gt
when you add new apps to INSTALLED_APPS
~
ordered

12. A QuerySet is iterable - and it executes its database query the first time you iterate over it.
search
iteration
DoesNotExist
db

13. This method is for controlling which database the QuerySet will be evaluated against if you are using more than one database. The only argument this method takes is the alias of a database - as defined in DATABASES.
gt
only(*fields)
lt
using(alias)

14. Each one of these is a Python class that subclasses django.db.models.Model. Each attribute of one of these represents a database field.
intermediate models
ForeignKey
model
&

15. restrictions on ________: (1) Your intermediate model must contain one - and only one - foreign key to the target model. (2) Your intermediate model must contain one - and only one - foreign key to the source model. (3) When defining a many-to-many r
regex
search
intermediate models
Q(question__startswith='Who') | ~Q(pub_date__year=2005)

16. A Manager method that returns a new QuerySet containing objects that match the given lookup parameters.
exact
Many-to-many relationship through an intermediate model
filter(**kwargs)
one-to-one relationship

17. Conjuntion operator for Q objects.
all()
only(*fields)
|
&

18. This query updates all the headlines with pub_date in 2007 to read 'Everything is the same'.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

19. To activate your models
|
default
edit your settings file and change the INSTALLED_APPS setting to add the name of the module that contains your models.py.
ForeignKey

20. This query finds all entries with an id greater than 4.
Entry.objects.filter(id__gt=4)
Entry.objects.filter(id__in=[1 - 3 - 4])
using(alias)
filter chaining

21. If True - this field is the primary key for the model.
contains
primary_key
get(**kwargs)
==

22. If this option is True - the field is allowed to be blank. Default is False.
reverse name
ordered
ForeignKey
blank

23. This model type is useful if you only want to modify the Python-level behavior of a model - without changing the models fields in any way. This creates a stand-in for the original model. You can create - delete and update instances of this new model
Meta class
delete()
Proxy model
iendswith

24. This object allows you to compare the value of a model field with another field on the same model. Django supports the use of addition - subtraction - multiplication - division and modulo arithmetic with these objects - both with constants and with o
exists()
iendswith
F()
slicing

25. These are specified as keyword arguments to the QuerySet methods filter() - exclude() and get(). These take the form field__lookuptype=value .
order_by(*fields)
Field lookups
when you add new apps to INSTALLED_APPS
model

26. If you are using this attribute on a ForeignKey or ManyToManyField - you must always specify a unique reverse name for the field.
only(*fields)
lt
related_name
get_absolute_url()

27. When to run syncdb
when you add new apps to INSTALLED_APPS
contains
Model metadata
isnull

28. These are "anything that's not a field" - such as ordering options (ordering) - database table name (db_table) - or human-readable singular and plural names (verbose_name and verbose_name_plural)
day
Model metadata
one-to-one relationship
startswith

29. Lookup type that corresponds to a boolean full-text search - taking advantage of full-text indexing. This is like contains but is significantly faster due to full-text indexing.
search
Abstract base class
Field lookups
edit your settings file and change the INSTALLED_APPS setting to add the name of the module that contains your models.py.

30. Disjunction operator for Q objects.
|
using(alias)
extra(select=None - where=None - params=None - tables=None - order_by=None - select_params=None)
help_text

31. Returns a ValuesQuerySet -- a QuerySet that returns dictionaries when used as an iterable - rather than model-instance objects.
values(*fields)
iregex
choices tuple
Manager methods

32. A Python "magic method" that returns a unicode "representation" of any object.
range
in_bulk(id_list)
__unicode__()
search

33. This style of inheritanc is useful when you're subclassing an existing model (perhaps something from another application entirely) and want each model to have its own database table. Here - each model in the hierarchy is a model all by itself.
annotate(args - *kwargs)
F()
only(*fields)
Multi-table inheritance

34. These methods are intended to do "table-wide" things.
Manager methods
intermediate models
Entry.objects.filter(id__in=[1 - 3 - 4])
add()

35. Lookup type that finds a case-insensitive regular expression match.
|
istartswith
ordered
iregex

36. Lookup type that yields an "exact" match. If you don't provide a lookup type -- that is - if your keyword argument doesn't contain a double underscore -- the lookup type is assumed to be of this sort.
QuerySet
Many-to-many relationship through an intermediate model
reverse name
exact

37. Lookup type for date/datetime fields that finds an exact month match. Takes an integer 1 (January) through 12
month
evaluation
defer(*fields)
Custom model methods

38. The value given in the absence of a specified value for the field. This can be a value or a callable object. If callable it will be called every time a new object is created.
default
get(**kwargs)
Entry.objects.filter(id__gt=4)
id field

39. This method returns tuples of values when iterated over. Each tuple contains the value from the respective field passed into the call to this method -- so the first item is the first field - etc.
evaluation
values_list(*fields)
using(alias)
Q()

40. This query finds all entries with an id in the list [1 - 3 - 4]
reverse()
Entry.objects.filter(id__in=[1 - 3 - 4])
in_bulk(id_list)
values(*fields)

41. By default - results returned by a QuerySet are ordered by the ordering tuple given by the ordering option in the model's Meta. You can override this on a per-QuerySet basis by using the this method.
iregex
order_by(*fields)
Entry.objects.filter(pub_date__range=(start_date - end_date))
edit your settings file and change the INSTALLED_APPS setting to add the name of the module that contains your models.py.

42. A convenience method for looking up an object with the given kwargs - creating one if necessary.
id field
&
exclude(**kwargs)
get_or_create(**kwargs)

43. A manager method that returns a new QuerySet containing objects that do not match the given lookup parameters.
default
exclude(**kwargs)
slicing
choices tuple

44. Performs an SQL update query for the specified fields - and returns the number of rows affected. This method is applied instantly and the only restriction on the QuerySet that is updated is that it can only update columns in the model's main table. F
Restrictions on field names
isnull
update(**kwargs)
iexact

45. Lookup type that returns results that fall into an inclusive date range.
when you add new apps to INSTALLED_APPS
range
db
one-to-one relationship

46. A Q object that asks for entries with a question value that start with 'Who' or do not have a publication date of 2005.

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

47. what the field _______ determines: (1) The database column type (e.g. INTEGER - VARCHAR); (2) The widget to use in Django's admin interface - if you care to use it (e.g. <input type="text"> - <select>); (3) The minimal validation requirements - used
class type
Many-to-many relationship through an intermediate model
OneToOneField
get_or_create(**kwargs)

48. This model method is used for updating a ManyToManyField.
lt
month
add()
~

49. Defined by a OneToOneField. You use it just like any other Field type: by including it as a class attribute of your model.
one-to-one relationship
Q(question__startswith='Who') | ~Q(pub_date__year=2005)
through argument
ForeignKey

50. Accomplish this by using the field name of related fields across models - separated by double underscores - until you get to the field you want. For example - to get all Entry objects with a Blog whose name is 'Beatles Blog': Entry.objects.filter(blo
relationship spanning
many-to-many relationship
when you add new apps to INSTALLED_APPS
update(**kwargs)