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Diffstat (limited to 'tests/modeltests/aggregation/models.py')
| -rw-r--r-- | tests/modeltests/aggregation/models.py | 379 |
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diff --git a/tests/modeltests/aggregation/models.py b/tests/modeltests/aggregation/models.py new file mode 100644 index 0000000000..4c89d7db3e --- /dev/null +++ b/tests/modeltests/aggregation/models.py @@ -0,0 +1,379 @@ +# coding: utf-8 +from django.db import models + +try: + sorted +except NameError: + from django.utils.itercompat import sorted # For Python 2.3 + +class Author(models.Model): + name = models.CharField(max_length=100) + age = models.IntegerField() + friends = models.ManyToManyField('self', blank=True) + + def __unicode__(self): + return self.name + +class Publisher(models.Model): + name = models.CharField(max_length=300) + num_awards = models.IntegerField() + + def __unicode__(self): + return self.name + +class Book(models.Model): + isbn = models.CharField(max_length=9) + name = models.CharField(max_length=300) + pages = models.IntegerField() + rating = models.FloatField() + price = models.DecimalField(decimal_places=2, max_digits=6) + authors = models.ManyToManyField(Author) + publisher = models.ForeignKey(Publisher) + pubdate = models.DateField() + + def __unicode__(self): + return self.name + +class Store(models.Model): + name = models.CharField(max_length=300) + books = models.ManyToManyField(Book) + original_opening = models.DateTimeField() + friday_night_closing = models.TimeField() + + def __unicode__(self): + return self.name + +class Entries(models.Model): + EntryID = models.AutoField(primary_key=True, db_column='Entry ID') + Entry = models.CharField(unique=True, max_length=50) + Exclude = models.BooleanField() + +class Clues(models.Model): + ID = models.AutoField(primary_key=True) + EntryID = models.ForeignKey(Entries, verbose_name='Entry', db_column = 'Entry ID') + Clue = models.CharField(max_length=150) + +# Tests on 'aggergate' +# Different backends and numbers. +__test__ = {'API_TESTS': """ +>>> from django.core import management +>>> try: +... from decimal import Decimal +... except: +... from django.utils._decimal import Decimal +>>> from datetime import date + +# Reset the database representation of this app. +# This will return the database to a clean initial state. +>>> management.call_command('flush', verbosity=0, interactive=False) + +# Empty Call - request nothing, get nothing. +>>> Author.objects.all().aggregate() +{} + +>>> from django.db.models import Avg, Sum, Count, Max, Min + +# Single model aggregation +# + +# Single aggregate +# Average age of Authors +>>> Author.objects.all().aggregate(Avg('age')) +{'age__avg': 37.4...} + +# Multiple aggregates +# Average and Sum of Author ages +>>> Author.objects.all().aggregate(Sum('age'), Avg('age')) +{'age__sum': 337, 'age__avg': 37.4...} + +# Aggreates interact with filters, and only +# generate aggregate values for the filtered values +# Sum of the age of those older than 29 years old +>>> Author.objects.all().filter(age__gt=29).aggregate(Sum('age')) +{'age__sum': 254} + +# Depth-1 Joins +# + +# On Relationships with self +# Average age of the friends of each author +>>> Author.objects.all().aggregate(Avg('friends__age')) +{'friends__age__avg': 34.07...} + +# On ManyToMany Relationships +# + +# Forward +# Average age of the Authors of Books with a rating of less than 4.5 +>>> Book.objects.all().filter(rating__lt=4.5).aggregate(Avg('authors__age')) +{'authors__age__avg': 38.2...} + +# Backward +# Average rating of the Books whose Author's name contains the letter 'a' +>>> Author.objects.all().filter(name__contains='a').aggregate(Avg('book__rating')) +{'book__rating__avg': 4.0} + +# On OneToMany Relationships +# + +# Forward +# Sum of the number of awards of each Book's Publisher +>>> Book.objects.all().aggregate(Sum('publisher__num_awards')) +{'publisher__num_awards__sum': 30} + +# Backward +# Sum of the price of every Book that has a Publisher +>>> Publisher.objects.all().aggregate(Sum('book__price')) +{'book__price__sum': Decimal("270.27")} + +# Multiple Joins +# + +# Forward +>>> Store.objects.all().aggregate(Max('books__authors__age')) +{'books__authors__age__max': 57} + +# Backward +# Note that the very long default alias may be truncated +>>> Author.objects.all().aggregate(Min('book__publisher__num_awards')) +{'book__publisher__num_award...': 1} + +# Aggregate outputs can also be aliased. + +# Average amazon.com Book rating +>>> Store.objects.filter(name='Amazon.com').aggregate(amazon_mean=Avg('books__rating')) +{'amazon_mean': 4.08...} + +# Tests on annotate() + +# An empty annotate call does nothing but return the same QuerySet +>>> Book.objects.all().annotate().order_by('pk') +[<Book: The Definitive Guide to Django: Web Development Done Right>, <Book: Sams Teach Yourself Django in 24 Hours>, <Book: Practical Django Projects>, <Book: Python Web Development with Django>, <Book: Artificial Intelligence: A Modern Approach>, <Book: Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp>] + +# Annotate inserts the alias into the model object with the aggregated result +>>> books = Book.objects.all().annotate(mean_age=Avg('authors__age')) +>>> books.get(pk=1).name +u'The Definitive Guide to Django: Web Development Done Right' + +>>> books.get(pk=1).mean_age +34.5 + +# On ManyToMany Relationships + +# Forward +# Average age of the Authors of each book with a rating less than 4.5 +>>> books = Book.objects.all().filter(rating__lt=4.5).annotate(Avg('authors__age')) +>>> sorted([(b.name, b.authors__age__avg) for b in books]) +[(u'Artificial Intelligence: A Modern Approach', 51.5), (u'Practical Django Projects', 29.0), (u'Python Web Development with Django', 30.3...), (u'Sams Teach Yourself Django in 24 Hours', 45.0)] + +# Count the number of authors of each book +>>> books = Book.objects.annotate(num_authors=Count('authors')) +>>> sorted([(b.name, b.num_authors) for b in books]) +[(u'Artificial Intelligence: A Modern Approach', 2), (u'Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp', 1), (u'Practical Django Projects', 1), (u'Python Web Development with Django', 3), (u'Sams Teach Yourself Django in 24 Hours', 1), (u'The Definitive Guide to Django: Web Development Done Right', 2)] + +# Backward +# Average rating of the Books whose Author's names contains the letter 'a' +>>> authors = Author.objects.all().filter(name__contains='a').annotate(Avg('book__rating')) +>>> sorted([(a.name, a.book__rating__avg) for a in authors]) +[(u'Adrian Holovaty', 4.5), (u'Brad Dayley', 3.0), (u'Jacob Kaplan-Moss', 4.5), (u'James Bennett', 4.0), (u'Paul Bissex', 4.0), (u'Stuart Russell', 4.0)] + +# Count the number of books written by each author +>>> authors = Author.objects.annotate(num_books=Count('book')) +>>> sorted([(a.name, a.num_books) for a in authors]) +[(u'Adrian Holovaty', 1), (u'Brad Dayley', 1), (u'Jacob Kaplan-Moss', 1), (u'James Bennett', 1), (u'Jeffrey Forcier ', 1), (u'Paul Bissex', 1), (u'Peter Norvig', 2), (u'Stuart Russell', 1), (u'Wesley J. Chun', 1)] + +# On OneToMany Relationships + +# Forward +# Annotate each book with the number of awards of each Book's Publisher +>>> books = Book.objects.all().annotate(Sum('publisher__num_awards')) +>>> sorted([(b.name, b.publisher__num_awards__sum) for b in books]) +[(u'Artificial Intelligence: A Modern Approach', 7), (u'Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp', 9), (u'Practical Django Projects', 3), (u'Python Web Development with Django', 7), (u'Sams Teach Yourself Django in 24 Hours', 1), (u'The Definitive Guide to Django: Web Development Done Right', 3)] + +# Backward +# Annotate each publisher with the sum of the price of all books sold +>>> publishers = Publisher.objects.all().annotate(Sum('book__price')) +>>> sorted([(p.name, p.book__price__sum) for p in publishers]) +[(u'Apress', Decimal("59.69")), (u'Morgan Kaufmann', Decimal("75.00")), (u'Prentice Hall', Decimal("112.49")), (u'Sams', Decimal("23.09"))] + +# Calls to values() are not commutative over annotate(). + +# Calling values on a queryset that has annotations returns the output +# as a dictionary +>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values() +[{'rating': 4.5, 'isbn': u'159059725', 'name': u'The Definitive Guide to Django: Web Development Done Right', 'pubdate': datetime.date(2007, 12, 6), 'price': Decimal("30..."), 'id': 1, 'publisher_id': 1, 'pages': 447, 'mean_age': 34.5}] + +>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values('pk', 'isbn', 'mean_age') +[{'pk': 1, 'isbn': u'159059725', 'mean_age': 34.5}] + +# Calling it with paramters reduces the output but does not remove the +# annotation. +>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values('name') +[{'name': u'The Definitive Guide to Django: Web Development Done Right', 'mean_age': 34.5}] + +# An empty values() call before annotating has the same effect as an +# empty values() call after annotating +>>> Book.objects.filter(pk=1).values().annotate(mean_age=Avg('authors__age')) +[{'rating': 4.5, 'isbn': u'159059725', 'name': u'The Definitive Guide to Django: Web Development Done Right', 'pubdate': datetime.date(2007, 12, 6), 'price': Decimal("30..."), 'id': 1, 'publisher_id': 1, 'pages': 447, 'mean_age': 34.5}] + +# Calling annotate() on a ValuesQuerySet annotates over the groups of +# fields to be selected by the ValuesQuerySet. + +# Note that an extra parameter is added to each dictionary. This +# parameter is a queryset representing the objects that have been +# grouped to generate the annotation + +>>> Book.objects.all().values('rating').annotate(n_authors=Count('authors__id'), mean_age=Avg('authors__age')).order_by('rating') +[{'rating': 3.0, 'n_authors': 1, 'mean_age': 45.0}, {'rating': 4.0, 'n_authors': 6, 'mean_age': 37.1...}, {'rating': 4.5, 'n_authors': 2, 'mean_age': 34.5}, {'rating': 5.0, 'n_authors': 1, 'mean_age': 57.0}] + +# If a join doesn't match any objects, an aggregate returns None +>>> authors = Author.objects.all().annotate(Avg('friends__age')).order_by('id') +>>> len(authors) +9 +>>> sorted([(a.name, a.friends__age__avg) for a in authors]) +[(u'Adrian Holovaty', 32.0), (u'Brad Dayley', None), (u'Jacob Kaplan-Moss', 29.5), (u'James Bennett', 34.0), (u'Jeffrey Forcier ', 27.0), (u'Paul Bissex', 31.0), (u'Peter Norvig', 46.0), (u'Stuart Russell', 57.0), (u'Wesley J. Chun', 33.6...)] + + +# The Count aggregation function allows an extra parameter: distinct. +# This restricts the count results to unique items +>>> Book.objects.all().aggregate(Count('rating')) +{'rating__count': 6} + +>>> Book.objects.all().aggregate(Count('rating', distinct=True)) +{'rating__count': 4} + +# Retreiving the grouped objects + +# When using Count you can also omit the primary key and refer only to +# the related field name if you want to count all the related objects +# and not a specific column +>>> explicit = list(Author.objects.annotate(Count('book__id'))) +>>> implicit = list(Author.objects.annotate(Count('book'))) +>>> explicit == implicit +True + +# Ordering is allowed on aggregates +>>> Book.objects.values('rating').annotate(oldest=Max('authors__age')).order_by('oldest', 'rating') +[{'rating': 4.5, 'oldest': 35}, {'rating': 3.0, 'oldest': 45}, {'rating': 4.0, 'oldest': 57}, {'rating': 5.0, 'oldest': 57}] + +>>> Book.objects.values('rating').annotate(oldest=Max('authors__age')).order_by('-oldest', '-rating') +[{'rating': 5.0, 'oldest': 57}, {'rating': 4.0, 'oldest': 57}, {'rating': 3.0, 'oldest': 45}, {'rating': 4.5, 'oldest': 35}] + +# It is possible to aggregate over anotated values +>>> Book.objects.all().annotate(num_authors=Count('authors__id')).aggregate(Avg('num_authors')) +{'num_authors__avg': 1.66...} + +# You can filter the results based on the aggregation alias. + +# Lets add a publisher to test the different possibilities for filtering +>>> p = Publisher(name='Expensive Publisher', num_awards=0) +>>> p.save() +>>> Book(name='ExpensiveBook1', pages=1, isbn='111', rating=3.5, price=Decimal("1000"), publisher=p, pubdate=date(2008,12,1)).save() +>>> Book(name='ExpensiveBook2', pages=1, isbn='222', rating=4.0, price=Decimal("1000"), publisher=p, pubdate=date(2008,12,2)).save() +>>> Book(name='ExpensiveBook3', pages=1, isbn='333', rating=4.5, price=Decimal("35"), publisher=p, pubdate=date(2008,12,3)).save() + +# Publishers that have: + +# (i) more than one book +>>> Publisher.objects.annotate(num_books=Count('book__id')).filter(num_books__gt=1).order_by('pk') +[<Publisher: Apress>, <Publisher: Prentice Hall>, <Publisher: Expensive Publisher>] + +# (ii) a book that cost less than 40 +>>> Publisher.objects.filter(book__price__lt=Decimal("40.0")).order_by('pk') +[<Publisher: Apress>, <Publisher: Apress>, <Publisher: Sams>, <Publisher: Prentice Hall>, <Publisher: Expensive Publisher>] + +# (iii) more than one book and (at least) a book that cost less than 40 +>>> Publisher.objects.annotate(num_books=Count('book__id')).filter(num_books__gt=1, book__price__lt=Decimal("40.0")).order_by('pk') +[<Publisher: Apress>, <Publisher: Prentice Hall>, <Publisher: Expensive Publisher>] + +# (iv) more than one book that costs less than $40 +>>> Publisher.objects.filter(book__price__lt=Decimal("40.0")).annotate(num_books=Count('book__id')).filter(num_books__gt=1).order_by('pk') +[<Publisher: Apress>] + +# Now a bit of testing on the different lookup types +# + +>>> Publisher.objects.annotate(num_books=Count('book')).filter(num_books__range=[1, 3]).order_by('pk') +[<Publisher: Apress>, <Publisher: Sams>, <Publisher: Prentice Hall>, <Publisher: Morgan Kaufmann>, <Publisher: Expensive Publisher>] + +>>> Publisher.objects.annotate(num_books=Count('book')).filter(num_books__range=[1, 2]).order_by('pk') +[<Publisher: Apress>, <Publisher: Sams>, <Publisher: Prentice Hall>, <Publisher: Morgan Kaufmann>] + +>>> Publisher.objects.annotate(num_books=Count('book')).filter(num_books__in=[1, 3]).order_by('pk') +[<Publisher: Sams>, <Publisher: Morgan Kaufmann>, <Publisher: Expensive Publisher>] + +>>> Publisher.objects.annotate(num_books=Count('book')).filter(num_books__isnull=True) +[] + +>>> p.delete() + +# Does Author X have any friends? (or better, how many friends does author X have) +>> Author.objects.filter(pk=1).aggregate(Count('friends__id')) +{'friends__id__count': 2.0} + +# Give me a list of all Books with more than 1 authors +>>> Book.objects.all().annotate(num_authors=Count('authors__name')).filter(num_authors__ge=2).order_by('pk') +[<Book: The Definitive Guide to Django: Web Development Done Right>, <Book: Artificial Intelligence: A Modern Approach>] + +# Give me a list of all Authors that have no friends +>>> Author.objects.all().annotate(num_friends=Count('friends__id', distinct=True)).filter(num_friends=0).order_by('pk') +[<Author: Brad Dayley>] + +# Give me a list of all publishers that have published more than 1 books +>>> Publisher.objects.all().annotate(num_books=Count('book__id')).filter(num_books__gt=1).order_by('pk') +[<Publisher: Apress>, <Publisher: Prentice Hall>] + +# Give me a list of all publishers that have published more than 1 books that cost less than 40 +>>> Publisher.objects.all().filter(book__price__lt=Decimal("40.0")).annotate(num_books=Count('book__id')).filter(num_books__gt=1) +[<Publisher: Apress>] + +# Give me a list of all Books that were written by X and one other author. +>>> Book.objects.all().annotate(num_authors=Count('authors__id')).filter(authors__name__contains='Norvig', num_authors__gt=1) +[<Book: Artificial Intelligence: A Modern Approach>] + +# Give me the average rating of all Books that were written by X and one other author. +#(Aggregate over objects discovered using membership of the m2m set) + +# Adding an existing author to another book to test it the right way +>>> a = Author.objects.get(name__contains='Norvig') +>>> b = Book.objects.get(name__contains='Done Right') +>>> b.authors.add(a) +>>> b.save() + +# This should do it +>>> Book.objects.all().annotate(num_authors=Count('authors__id')).filter(authors__name__contains='Norvig', num_authors__gt=1).aggregate(Avg('rating')) +{'rating__avg': 4.25} +>>> b.authors.remove(a) + +# Give me a list of all Authors that have published a book with at least one other person +# (Filters over a count generated on a related object) +# +# Cheating: [a for a in Author.objects.all().annotate(num_coleagues=Count('book__authors__id'), num_books=Count('book__id', distinct=True)) if a.num_coleagues - a.num_books > 0] +# F-Syntax is required. Will be fixed after F objects are available + +# Tests on fields with non-default table and column names. +>>> Clues.objects.values('EntryID__Entry').annotate(Appearances=Count('EntryID'), Distinct_Clues=Count('Clue', distinct=True)) +[] + +# Aggregates also work on dates, times and datetimes +>>> Publisher.objects.annotate(earliest_book=Min('book__pubdate')).order_by('earliest_book').values() +[{'earliest_book': datetime.date(1991, 10, 15), 'num_awards': 9, 'id': 4, 'name': u'Morgan Kaufmann'}, {'earliest_book': datetime.date(1995, 1, 15), 'num_awards': 7, 'id': 3, 'name': u'Prentice Hall'}, {'earliest_book': datetime.date(2007, 12, 6), 'num_awards': 3, 'id': 1, 'name': u'Apress'}, {'earliest_book': datetime.date(2008, 3, 3), 'num_awards': 1, 'id': 2, 'name': u'Sams'}] + +>>> Store.objects.aggregate(Max('friday_night_closing'), Min("original_opening")) +{'friday_night_closing__max': datetime.time(23, 59, 59), 'original_opening__min': datetime.datetime(1945, 4, 25, 16, 24, 14)} + +# values_list() can also be used + +>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values_list('pk', 'isbn', 'mean_age') +[(1, u'159059725', 34.5)] + +>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values_list('isbn') +[(u'159059725',)] + +>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values_list('mean_age') +[(34.5,)] + +>>> Book.objects.filter(pk=1).annotate(mean_age=Avg('authors__age')).values_list('mean_age', flat=True) +[34.5] + +"""} |
