Test your basic knowledge |

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. A Python "magic method" that returns a unicode "representation" of any object.






2. Exception raised by get(**kwargs) if no items match the query.






3. A QuerySet is iterable - and it executes its database query the first time you iterate over it.






4. (1) These cannot be Python reserved words - because that would result in a Python syntax error. (2) These cannot contain more than one underscore in a row - due to the way Django's query lookup syntax works.






5. A Manager method that returns a new QuerySet containing objects that match the given lookup parameters.






6. Lookup type that returns results less than a given value.






7. Defines a many-to-one relationship. ou use it just like any other Field type: by including it as a class attribute of your model.






8. 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.






9. Use this method to reverse the order in which a queryset's elements are returned. Calling this method a second time restores the ordering back to the normal direction.






10. 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






11. 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.






12. This query finds all entries between a start date of start_date and an end date of end_date.






13. Lookup type that finds a case-sensitive regular expression match.






14. 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.






15. These add custom "row-level" functionality to your objects. These act on a particular model instance.






16. Here - you can't use add - create - or assignment (i.e. - beatles.members = [...]) to create relationships. You need to specify all the detail for the relationship required by the intermediate model.






17. Returns a new QuerySet that uses SELECT DISTINCT in its SQL query. This eliminates duplicate rows from the query results.






18. Returns a copy of the current QuerySet (or QuerySet subclass you pass in). This can be useful in some situations where you might want to pass in either a model manager or a QuerySet and do further filtering on the result. You can safely call all() on






19. A manager method which returns a single object. If there are no results that match the query - this method will raise a DoesNotExist exception. If more than one item matches this query - the method will raise MultipleObjectsReturned.






20. Lookup type that tests for inclusion in a case-sensitive fashion.






21. A manager method that returns a new QuerySet containing objects that do not match the given lookup parameters.






22. Negation operator for Q objects.






23. 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


24. A convenience method for constructing an object and saving it all in one step.






25. A Q object that encapsulates queries for entries with a question value that starts with 'What' in a case-insensitive fashion.

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26. The database that will be used if this query is executed now






27. Operator for comparing two model instances for equality. Behind the scenes - it compares the primary key values of two models.






28. Lookup type for date/datetime fields that finds an exact day match.






29. Lookup type for date/datetime fields that finds a 'day of the week' match.






30. Returns a QuerySet that will automatically "follow" foreign-key relationships - selecting that additional related-object data when it executes its query. This is a performance booster which results in (sometimes much) larger queries but means later u






31. A convenience method for looking up an object with the given kwargs - creating one if necessary.






32. When to run syncdb






33. Returns a new QuerySet containing objects that match the given lookup parameters.






34. 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






35. This represents a collection of objects from your database. It can have zero - one or many filters.






36. 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.






37. 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.






38. 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






39. Lookup type that finds a case-insensitive regular expression match.






40. 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.






41. Keyword shortcut for looking up an object by primary key.






42. Defined by a OneToOneField. You use it just like any other Field type: by including it as a class attribute of your model.






43. Lookup type that returns results with a case-sensitive end sequence.






44. 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






45. Manager method used to retrieve every object in a model.






46. If you pickle a QuerySet - this will force all the results to be loaded into memory prior to pickling. When you unpickle a QuerySet - it contains the results at the moment it was pickled - rather than the results that are currently in the database.






47. Fields are specified by these






48. In some complex data-modeling situations - your models might contain a lot of fields - some of which could contain a lot of data (for example - text fields) - or require expensive processing to convert them to Python objects. If you are using the res






49. 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.






50. The default for this is the name of the child class followed by '_set'.