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. Extra text to be displayed under the field on the object's admin form to provide assistance to users. It's useful for documentation even if your object doesn't have an admin form.






2. 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.






3. If True - this field is the primary key for the model.






4. 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.






5. 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






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






7. Takes the ouput of one filter and uses it as input for another filter. This works because a refinement of a QuerySet is itself a QuerySet.






8. If True - the table does not permit duplicate values for this field.






9. When to run syncdb






10. 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()






11. This query finds all entries with an id in the list [1 - 3 - 4]






12. 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.






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






14. 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






15. These are specified as keyword arguments to the QuerySet methods filter() - exclude() and get(). These take the form field__lookuptype=value .






16. Lookup type that returns results greater than or equal to a given value.






17. True if the QuerySet has an order_by() clause or a default ordering on the model. False otherwise.






18. This method immediately deletes the object and has no return value.






19. Negation operator for Q objects.






20. Used to get a QuerySet for a model. This is called 'objects' by default.






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






22. Lookup type that returns results greater than a given value.






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






24. 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.






25. Defined by django.db.models.ForeignKey. You use it just like any other Field type: by including it as a class attribute of your model.






26. Can be used to remove all many-to-many relationships for an instance






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






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






29. 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.






30. Returns an integer representing the number of objects in the database matching the QuerySet. This never raises exceptions.






31. If you are using this attribute on a ForeignKey or ManyToManyField - you must always specify a unique reverse name for the field.






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






33. Lookup type that yields a case-insensitive match.






34. In this case - an intermediate model can have multiple foreign keys to the source model. Here - two foreign keys to the same model are permitted - but they will be treated as the two (different) sides of the many-to-many relation.






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

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


36. 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






37. 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






38. This is a criterion that narrow down a QuerySet based on given parameters.






39. Evaluates the QuerySet (by performing the query) and returns an iterator over the results. A QuerySet typically caches its results internally so that repeated evaluations do not result in additional queries; this method will instead read results dire






40. Lookup type that returns results with a case-insensitive end sequence.






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






42. Lookup type that takes either True or False and corresponds to SQL queries of IS NULL and IS NOT NULL - respectively.






43. Sometimes - the Django query syntax by itself can't easily express a complex WHERE clause. For these edge cases - Django provides this QuerySet modifier -- a hook for injecting specific clauses into the SQL generated by a QuerySet.






44. This model method is used for updating a ManyToManyField.






45. 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.






46. This method is more or less the opposite of defer(). You call it with the fields that should not be deferred when retrieving a model. If you have a model where almost all the fields need to be deferred - using this method to specify the complementary






47. 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.






48. Lookup type that returns results with a case-sensitive start sequence.






49. Returns the most recent object in the table - by date - using the field_name provided as the date field.






50. 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