SUBJECTS
|
BROWSE
|
CAREER CENTER
|
POPULAR
|
JOIN
|
LOGIN
Business Skills
|
Soft Skills
|
Basic Literacy
|
Certifications
About
|
Help
|
Privacy
|
Terms
|
Email
Search
Test your basic knowledge |
Django Queryset
Start Test
Study First
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. Returns an EmptyQuerySet -- a QuerySet that always evaluates to an empty list. This can be used in cases where you know that you should return an empty result set and your caller is expecting a QuerySet object (instead of returning an empty list - fo
none()
id field
lte
blank
2. This class type is useful when you just want to use the parent class to hold information that you don't want to have to type out for each child model. This class isn't going to ever be used in isolation. When it is used as a base class for other mode
Abstract base class
all()
values(*fields)
choices
3. An iterable (e.g. - a list or tuple) of 2-tuples to use as options for this field. If this is given - Django's admin will use a select box instead of the standard text field and will limit options to those given.
iregex
reverse name
choices
iterator()
4. Lookup type for date/datetime fields that finds a 'day of the week' match.
all()
through argument
week_day
endswith
5. Used to get a QuerySet for a model. This is called 'objects' by default.
defer(*fields)
slicing
null
Manager
6. Lookup type that returns results with a case-insensitive end sequence.
many-to-one relationship
DoesNotExist
lte
iendswith
7. Lookup type that tests for inclusion in a case-sensitive fashion.
Custom model methods
update()
contains
add()
8. This query finds all entries between a start date of start_date and an end date of end_date.
class attributes
order_by(*fields)
Entry.objects.filter(pub_date__range=(start_date - end_date))
Multi-table inheritance
9. Exception raised by get(**kwargs) if more than one item matches the query.
MultipleObjectsReturned
blank
delete()
id field
10. Returns True if the QuerySet contains any results - and False if not. This tries to perform the query in the simplest and fastest way possible - but it does execute nearly the same query. This means that calling this method on a queryset is faster th
exists()
get_or_create(**kwargs)
Manager
endswith
11. 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
relationship spanning
none()
class type
reverse()
12. A Python "magic method" that returns a unicode "representation" of any object.
Entry.objects.filter(id__in=[1 - 3 - 4])
__unicode__()
values_list(*fields)
iteration
13. This represents a collection of objects from your database. It can have zero - one or many filters.
defer(*fields)
relationship spanning
exists()
QuerySet
14. 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
evaluation
Proxy model
endswith
Many-to-many relationship through an intermediate model
15. 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.
Field lookups
one-to-one relationship
default
exclude(**kwargs)
16. Lookup type that returns results less than a given value.
get(**kwargs)
lt
exact
Meta class
17. Lookup type that returns results less than or equal to a given value.
lte
id field
contains
pickling
18. Manager method used to retrieve every object in a model.
all()
Entry.objects.filter(pub_date__range=(start_date - end_date))
Q()
startswith
19. This query finds all entries with an id greater than 4.
month
get_absolute_url()
Meta class
Entry.objects.filter(id__gt=4)
20. Lookup type that finds a case-sensitive regular expression match.
contains
related_name
regex
when you add new apps to INSTALLED_APPS
21. When to run syncdb
week_day
~
Q()
when you add new apps to INSTALLED_APPS
22. Lookup type that finds a case-insensitive regular expression match.
&
intermediate models
iregex
only(*fields)
23. These are specified as keyword arguments to the QuerySet methods filter() - exclude() and get(). These take the form field__lookuptype=value .
in
Field lookups
choices tuple
filter
24. This object encapsulates a collection of keyword arguments - with the keys being field lookup types. These objects can be combined using the & and | operators - as well as negated with the ~ operator.
Q(question__istartswith='What')
add()
get(**kwargs)
Q()
25. Lookup type that returns results with a case-insensitive start sequence.
aggregate(args - *kwargs)
filter(**kwargs)
get(**kwargs)
istartswith
26. a QuerySet can be sliced - using Python's array-slicing syntax.
order_by(*fields)
slicing
Manager methods
choices tuple
27. If True - this field is the primary key for the model.
iendswith
primary_key
Q(question__startswith='Who') | ~Q(pub_date__year=2005)
Custom model methods
28. This field is added automatically - but this behavior can be overridden
gte
through argument
Entry.objects.filter(pub_date__range=(start_date - end_date))
id field
29. Evaluation happens upon use the "step" parameter of slice syntax - the first time you iterate over it - when pickling or caching results - upon calling repr() - upon calling len() - upon calling list() - upon calling bool()
clear() method
evaluation
Custom model methods
edit your settings file and change the INSTALLED_APPS setting to add the name of the module that contains your models.py.
30. The first element in this iterable is the value that will be stored in the database - the second element will be displayed by the admin interface - or in a ModelChoiceField.
intermediate models
Entry.objects.filter(id__in=[1 - 3 - 4])
choices tuple
regex
31. A QuerySet is iterable - and it executes its database query the first time you iterate over it.
iteration
all()
regex
delete()
32. This method immediately deletes the object and has no return value.
Q()
delete()
Model metadata
get_absolute_url()
33. Operator for comparing two model instances for equality. Behind the scenes - it compares the primary key values of two models.
lt
==
iexact
iendswith
34. If True - the table does not permit duplicate values for this field.
ordered
year
relationship spanning
unique
35. Specifies the model that will be used to govern the many-to-many relationship. You can then put extra fields on the intermediate model. The intermediate model is associated with the ManyToManyField using this to point to the model that will act as an
through argument
extra(select=None - where=None - params=None - tables=None - order_by=None - select_params=None)
slicing
iterator()
36. This query finds all entries with an id in the list [1 - 3 - 4]
through argument
Entry.objects.filter(id__in=[1 - 3 - 4])
Abstract base class
values_list(*fields)
37. 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.
ManyToManyField
Manager
default
get_absolute_url()
38. 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
DoesNotExist
get_absolute_url()
exact
F()
39. Lookup type that returns results that fall into an inclusive date range.
choices tuple
extra(select=None - where=None - params=None - tables=None - order_by=None - select_params=None)
delete()
range
40. Defines a many-to-many relationship. You use it just like any other Field type: by including it as a class attribute of your model.
Manager methods
in_bulk(id_list)
ManyToManyField
filter(**kwargs)
41. 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.
annotate(args - *kwargs)
values_list(*fields)
Q(question__startswith='Who') | ~Q(pub_date__year=2005)
month
42. 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
ordered
filter
pickling
relationship spanning
43. To activate your models
regex
istartswith
edit your settings file and change the INSTALLED_APPS setting to add the name of the module that contains your models.py.
iendswith
44. 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
45. The database that will be used if this query is executed now
intermediate models
db
F()
many-to-many relationship
46. True if the QuerySet has an order_by() clause or a default ordering on the model. False otherwise.
endswith
null
week_day
ordered
47. This model method saves a model instance to the database. This method has no return value.
in_bulk(id_list)
isnull
save()
through argument
48. Returns an integer representing the number of objects in the database matching the QuerySet. This never raises exceptions.
Multi-table inheritance
delete()
all()
count()
49. Defines a one-to-one relationship. You use it just like any other Field type: by including it as a class attribute of your model.
OneToOneField
add()
delete()
id field
50. Takes a list of primary-key values and returns a dictionary mapping each primary-key value to an instance of the object with the given ID.
ForeignKey
help_text
iterator()
in_bulk(id_list)