diff options
Diffstat (limited to 'docs/topics/db')
| -rw-r--r-- | docs/topics/db/aggregation.txt | 14 | ||||
| -rw-r--r-- | docs/topics/db/queries.txt | 20 |
2 files changed, 23 insertions, 11 deletions
diff --git a/docs/topics/db/aggregation.txt b/docs/topics/db/aggregation.txt index 9f98504c0c..cd53f73c74 100644 --- a/docs/topics/db/aggregation.txt +++ b/docs/topics/db/aggregation.txt @@ -222,12 +222,14 @@ Combining multiple aggregations Combining multiple aggregations with ``annotate()`` will :ticket:`yield the wrong results <10060>` because joins are used instead of subqueries: +.. code-block:: pycon + >>> book = Book.objects.first() >>> book.authors.count() 2 >>> book.store_set.count() 3 - >>> q = Book.objects.annotate(Count('authors'), Count('store')) + >>> q = Book.objects.annotate(Count("authors"), Count("store")) >>> q[0].authors__count 6 >>> q[0].store__count @@ -237,7 +239,11 @@ For most aggregates, there is no way to avoid this problem, however, the :class:`~django.db.models.Count` aggregate has a ``distinct`` parameter that may help: - >>> q = Book.objects.annotate(Count('authors', distinct=True), Count('store', distinct=True)) +.. code-block:: pycon + + >>> q = Book.objects.annotate( + ... Count("authors", distinct=True), Count("store", distinct=True) + ... ) >>> q[0].authors__count 2 >>> q[0].store__count @@ -514,7 +520,9 @@ the annotation is computed over all members of the group. For example, consider an author query that attempts to find out the average rating of books written by each author: - >>> Author.objects.annotate(average_rating=Avg('book__rating')) +.. code-block:: pycon + + >>> Author.objects.annotate(average_rating=Avg("book__rating")) This will return one result for each author in the database, annotated with their average book rating. diff --git a/docs/topics/db/queries.txt b/docs/topics/db/queries.txt index 6dfe97f317..65e84ecdc4 100644 --- a/docs/topics/db/queries.txt +++ b/docs/topics/db/queries.txt @@ -448,6 +448,8 @@ can specify the field name suffixed with ``_id``. In this case, the value parameter is expected to contain the raw value of the foreign model's primary key. For example: +.. code-block:: pycon + >>> Entry.objects.filter(blog_id=4) If you pass an invalid keyword argument, a lookup function will raise @@ -610,40 +612,42 @@ contained in a single :meth:`~django.db.models.query.QuerySet.filter` call. As the second (more permissive) query chains multiple filters, it performs multiple joins to the primary model, potentially yielding duplicates. + .. code-block:: pycon + >>> from datetime import date - >>> beatles = Blog.objects.create(name='Beatles Blog') - >>> pop = Blog.objects.create(name='Pop Music Blog') + >>> beatles = Blog.objects.create(name="Beatles Blog") + >>> pop = Blog.objects.create(name="Pop Music Blog") >>> Entry.objects.create( ... blog=beatles, - ... headline='New Lennon Biography', + ... headline="New Lennon Biography", ... pub_date=date(2008, 6, 1), ... ) <Entry: New Lennon Biography> >>> Entry.objects.create( ... blog=beatles, - ... headline='New Lennon Biography in Paperback', + ... headline="New Lennon Biography in Paperback", ... pub_date=date(2009, 6, 1), ... ) <Entry: New Lennon Biography in Paperback> >>> Entry.objects.create( ... blog=pop, - ... headline='Best Albums of 2008', + ... headline="Best Albums of 2008", ... pub_date=date(2008, 12, 15), ... ) <Entry: Best Albums of 2008> >>> Entry.objects.create( ... blog=pop, - ... headline='Lennon Would Have Loved Hip Hop', + ... headline="Lennon Would Have Loved Hip Hop", ... pub_date=date(2020, 4, 1), ... ) <Entry: Lennon Would Have Loved Hip Hop> >>> Blog.objects.filter( - ... entry__headline__contains='Lennon', + ... entry__headline__contains="Lennon", ... entry__pub_date__year=2008, ... ) <QuerySet [<Blog: Beatles Blog>]> >>> Blog.objects.filter( - ... entry__headline__contains='Lennon', + ... entry__headline__contains="Lennon", ... ).filter( ... entry__pub_date__year=2008, ... ) |
