Creating a new cluster is neither required not recommendable for
most users. The previous section explains how to create a user
with sufficient permissions to automatically create a database
during tests.

Warnings could escape depending on the order in which tests were run.

One handler in WSGIServer, to catch the error when raised from
SocketServer.BaseServer's finish_request, and one in WSGIRequestHandler
(by creating a subclass of ServerHandler), to catch the error when
raised in wsgiref.handlers.BaseHandler's finish_response.

If no changes that need migrations are found, `makemigrations --exit`
exits with error code 1.

Also removed Query.join_map. This structure was used to speed up join
reuse calculation. Initial benchmarking shows that this isn't actually
needed. If there are use cases where the removal has real-world
performance implications, it should be relatively straightforward to
reintroduce it as map {alias: [Join-like objects]}.

Thanks to github aliases dbrgn, carljm, slurms, dfunckt, and timgraham
for reviews.

Thanks to Berker Peksag and Tim Graham for the review and suggestions.

Thanks Jonathan Lindén for the initial patch, and Tim Graham
and Gabe Jackson for the suggestions.

Refs #20432 and #23746.

Refs #23641.

Aggregation over subquery produced syntactically incorrect queries in
some cases as Django didn't ensure that source expressions of the
aggregation were present in the subquery.

The .dates() queries were implemented by using custom Query, QuerySet,
and Compiler classes. Instead implement them by using expressions and
database converters APIs.

Refs #23677.

Thanks to Tim for the review.

refs #23754, #23862

This change allows dynamically created inlines "Add related" button to work
correcly as long as their associated foreign key is pointing to the primary
key of the related model.

Thanks to amorce for the report, Julien Phalip for the initial patch,
and Collin Anderson for the review.

Thanks Redouane Zait for the report.