... s . IntegerField () price = models . DecimalField ( max_digits = 10 , decimal_places = 2 ) rating = models . FloatField () authors = models . ManyToManyField ( Author ) publisher = models . ForeignKey ( Publisher , on_delete = models . CASCADE ) pubdate ... 場合です: # Build an annotated queryset >>> from django.db.models import Count >>> q = Book . objects . annotate ( Count ( "authors" )) # Interrogate the first object in the queryset >>> q [ 0 ] <Book: The Definitive Guide to Django> >>> q [ 0 ] . author ... s__count 2 # Interrogate the second object in the queryset >>> q [ 1 ] <Book: Practical Django Projects> >>> q [ 1 ] . authors__count 1 aggregate() と同様に、アノテーションの名前は集計関数の名前と集計されるフィールドの名前から自動的に生成されます。ア ... ... s . IntegerField () price = models . DecimalField ( max_digits = 10 , decimal_places = 2 ) rating = models . FloatField () authors = models . ManyToManyField ( Author ) publisher = models . ForeignKey ( Publisher , on_delete = models . CASCADE ) pubdate ... 場合です: # Build an annotated queryset >>> from django.db.models import Count >>> q = Book . objects . annotate ( Count ( "authors" )) # Interrogate the first object in the queryset >>> q [ 0 ] <Book: The Definitive Guide to Django> >>> q [ 0 ] . author ... s__count 2 # Interrogate the second object in the queryset >>> q [ 1 ] <Book: Practical Django Projects> >>> q [ 1 ] . authors__count 1 aggregate() と同様に、アノテーションの名前は集計関数の名前と集計されるフィールドの名前から自動的に生成されます。ア ... ... ody_text = models . TextField () pub_date = models . DateField () mod_date = models . DateField ( default = date . today ) authors = models . ManyToManyField ( Author ) number_of_comments = models . IntegerField ( default = 0 ) number_of_pingbacks = mod ... ェクトに追加しています: >>> from blog.models import Author >>> joe = Author . objects . create ( name = "Joe" ) >>> entry . authors . add ( joe ) 複数のレコードを ManyToManyField に一気に追加するには、 add() の呼び出しに複数の引数を含めてください: >>> jo ... eorge = Author . objects . create ( name = "George" ) >>> ringo = Author . objects . create ( name = "Ringo" ) >>> entry . authors . add ( john , paul , george , ringo ) もし間違った型のオブジェクトを設定もしくは追加しようとすれば Django はエラーを発生さ ... ... ody_text = models . TextField () pub_date = models . DateField () mod_date = models . DateField ( default = date . today ) authors = models . ManyToManyField ( Author ) number_of_comments = models . IntegerField ( default = 0 ) number_of_pingbacks = mod ... ェクトに追加しています: >>> from blog.models import Author >>> joe = Author . objects . create ( name = "Joe" ) >>> entry . authors . add ( joe ) 複数のレコードを ManyToManyField に一気に追加するには、 add() の呼び出しに複数の引数を含めてください: >>> jo ... eorge = Author . objects . create ( name = "George" ) >>> ringo = Author . objects . create ( name = "Ringo" ) >>> entry . authors . add ( john , paul , george , ringo ) もし間違った型のオブジェクトを設定もしくは追加しようとすれば Django はエラーを発生さ ... ... 値を先の values() 句に追加してください。例えば: >>> from django.db.models import Count >>> Blog . objects . values ( "entry__authors" , entries = Count ( "entry" )) <QuerySet [{'entry__authors': 1, 'entries': 20}, {'entry__authors': 1, 'entries': 13}]> >> ... > Blog . objects . values ( "entry__authors" ) . annotate ( entries = Count ( "entry" )) <QuerySet [{'entry__authors': 1, 'entries': 33}]> いくつかの際どいポイントにつ ... om django.db.models.functions import Lower >>> CharField . register_lookup ( Lower ) >>> Blog . objects . values ( "entry__authors__name__lower" ) . annotate ( entries = Count ( "entry" )) <QuerySet [{'entry__authors__name__lower': 'test author', 'entri ... ... 値を先の values() 句に追加してください。例えば: >>> from django.db.models import Count >>> Blog . objects . values ( "entry__authors" , entries = Count ( "entry" )) <QuerySet [{'entry__authors': 1, 'entries': 20}, {'entry__authors': 1, 'entries': 13}]> >> ... > Blog . objects . values ( "entry__authors" ) . annotate ( entries = Count ( "entry" )) <QuerySet [{'entry__authors': 1, 'entries': 33}]> いくつかの際どいポイントにつ ... om django.db.models.functions import Lower >>> CharField . register_lookup ( Lower ) >>> Blog . objects . values ( "entry__authors__name__lower" ) . annotate ( entries = Count ( "entry" )) <QuerySet [{'entry__authors__name__lower': 'test author', 'entri ... ... odels . CharField ( max_length = 1 , choices = { "A" : _ ( "Author" ), "E" : _ ( "Editor" )}) people = models . Manager () authors = AuthorManager () editors = EditorManager () この例では、 Person.authors.all() 、 Person.editors.all() 、 Person.people.a ... カスタムの QuerySet で定義したメソッドは Manager でも実装する必要があります: class PersonQuerySet ( models . QuerySet ): def authors ( self ): return self . filter ( role = "A" ) def editors ( self ): return self . filter ( role = "E" ) class PersonManage ... r ( models . Manager ): def get_queryset ( self ): return PersonQuerySet ( self . model , using = self . _db ) def authors ( self ): return self . get_queryset () . authors () def editors ( self ): return self . get_queryset () . editors () clas ... ... ping to avoid repetition and maintain consistent output. Basic syntax ¶ A partial can be defined using the partialdef tag: authors.html ¶ {% partialdef user-info %} < div id = "user-info- {{ user.username }} " > < h3 > {{ user.name }} </ h3 > < p > {{ u ... rendered using the partial tag: {% partial user-info %} Fragment reuse ¶ A template fragment can be reused multiple times: authors.html ¶ {% block content %} < h2 > Authors </ h2 > {% for user in authors %} {% partial user-info %} {% endfor %} < h2 > Ed ... % endpartialdef %} {# Other page content here. #} {# Reuse later elsewhere in the template. #} < section class = "featured-authors" > < h2 > Featured Authors </ h2 > {% for user in featured %} {% partial user-info %} {% endfor %} </ section > Accessing ... ... ping to avoid repetition and maintain consistent output. Basic syntax ¶ A partial can be defined using the partialdef tag: authors.html ¶ {% partialdef user-info %} < div id = "user-info- {{ user.username }} " > < h3 > {{ user.name }} </ h3 > < p > {{ u ... rendered using the partial tag: {% partial user-info %} Fragment reuse ¶ A template fragment can be reused multiple times: authors.html ¶ {% block content %} < h2 > Authors </ h2 > {% for user in authors %} {% partial user-info %} {% endfor %} < h2 > Ed ... % endpartialdef %} {# Other page content here. #} {# Reuse later elsewhere in the template. #} < section class = "featured-authors" > < h2 > Featured Authors </ h2 > {% for user in featured %} {% partial user-info %} {% endfor %} </ section > Accessing ... ... odels . CharField ( max_length = 1 , choices = { "A" : _ ( "Author" ), "E" : _ ( "Editor" )}) people = models . Manager () authors = AuthorManager () editors = EditorManager () この例では、 Person.authors.all() 、 Person.editors.all() 、 Person.people.a ... カスタムの QuerySet で定義したメソッドは Manager でも実装する必要があります: class PersonQuerySet ( models . QuerySet ): def authors ( self ): return self . filter ( role = "A" ) def editors ( self ): return self . filter ( role = "E" ) class PersonManage ... r ( models . Manager ): def get_queryset ( self ): return PersonQuerySet ( self . model , using = self . _db ) def authors ( self ): return self . get_queryset () . authors () def editors ( self ): return self . get_queryset () . editors () clas ... 2026年10月08日