AddField
Adds a field to a model with optional preserve_default.
Admin site
Automated admin interface, one of Django's most popular features.
aggregate()
Returns a dictionary of aggregate values over the QuerySet.
AlterIndexTogether ¶
AlterModelManagers ¶
AlterModelOptions ¶
AlterModelTable ¶
AlterModelTableComment ¶
AlterOrderWithRespectTo ¶
AlterUniqueTogether ¶
errors.as_json()
Returns errors serialized as JSON.
as_view() classmethod
Deploys a class-based view into a URL pattern, assigning arguments onto the request instance.
Bound and unbound forms
A Form instance is either bound to a set of data or unbound.
Built-in tags and filters
Built-in libraries can be used without the load tag.
Bulk methods
Create, update, insert, and remove objects in bulk to reduce query counts.
Class-based views
Built-in display and editing views using mixins.
Class-based views mixins
Simple, single object, multiple object, editing and date-based mixins extend base views.
Comparison and conversion functions
Cast, Coalesce, Collate, Greatest, Least, NullIf.
Context objects
Populates and renders a context, optionally with a request via RequestContext.
CreateModel
Creates a new model in project history and a matching database table.
Date functions
Extract, Now, Trunc.
DefaultStorage
Provides lazy access to the default storage system defined by the default key in STORAGES.
QuerySet.defer() and only()
Avoid retrieving fields you don't need from the database.
DeleteModel
Deletes the model from project history and its table from the database.
Deprecation warnings
Deprecated methods remain in the API for at least two feature releases and issue warnings when called.
Engine class
Configures dirs, loaders, context processors, autoescape, and other template options.
errors
Dictionary of error messages keyed by field name.
File uploads
File objects, storage API, managing files, and custom storage.
FileSystemStorage
Implements basic file storage on a local filesystem, inheriting from Storage.
filter()
Returns a new QuerySet containing objects that match the given lookup parameters.
Generic date views
ArchiveIndexView, YearArchiveView, MonthArchiveView, WeekArchiveView, DayArchiveView, TodayArchiveView and DateDetailView.
Generic display views
DetailView and ListView for displaying object details and lists.
Generic editing views
FormView, CreateView, UpdateView and DeleteView for editing data.
Geographic framework
Geographic framework for building GIS web applications.
get_alternative_name()
get_valid_name()
Returns a filename suitable for the underlying storage system.
Internationalization and localization
InMemoryStorage
Memory-based file storage with no persistence, useful for speeding up tests.
Internal API marking
Objects prefixed with a leading underscore are internal APIs that may change.
is_valid()
Runs validation on a bound form and returns a boolean.
QuerySet.iterator()
Reduces memory usage when working with a large number of objects.
JSON functions
JSONArray, JSONObject.
Math functions
Abs, ACos, ASin, ATan, ATan2, Ceil, Cos, Cot, Degrees, Exp, Floor, Ln, Log, Mod, Pi, Power, Radians, Random, Round, Sign, Sin, Sqrt, Tan.
Middleware
Built-in middleware classes for request/response processing.
Migration Operations ¶
Migrations
Introduction to Migrations and schema operations.
_open() method
Required method called by Storage.open() to open files.
Prefetch() objects
Allows customizing prefetch_related() operations.
prefetch_related()
Returns a QuerySet that fetches related objects in a separate batch query.
Backwards-compatible aliases
Public APIs will not be moved or renamed without providing backwards-compatible aliases.
Q() objects
Encapsulates keyword arguments for complex, reusable query conditions.
QuerySet API
QuerySet method reference for making queries.
QuerySet.explain()
Provides detailed information about how the database executes a query, including indexes and joins used.
RawSQL and raw SQL
Allows explicit SQL to be added to a query when the ORM is not powerful enough.
RemoveField
Removes a field from a model.
RenameField
Renames a field on a model.
RenameModel ¶
RunPython
Special operation for running Python data migrations.
RunSQL
Special operation for manual SQL database manipulation.
_save() method
Called by Storage.save() to save file content.
Schema Operations ¶
select_related()
Returns a QuerySet that follows foreign-key relationships, selecting related object data.
select_related() and prefetch_related()
Retrieve related objects efficiently by reducing the number of database queries.
SeparateDatabaseAndState
Special operation separating database and state changes.
Storage class
Standardized API for storing files with default behaviors that backends inherit or override.
Storage subclass
Custom storage systems must subclass django.core.files.storage.Storage.
storages registry
Dictionary-like object retrieving a storage instance by alias defined in STORAGES.
Template loaders
Loader classes import templates from filesystem, app directories, or custom sources.
Testing
Writing and running tests with included testing tools.
Testing tools
Introduction, writing and running tests, and included testing tools.
Text functions
Chr, Concat, Left, Length, Lower, LPad, LTrim, MD5, Ord, Repeat, Replace, Reverse, Right, RPad, RTrim, SHA1/SHA224/SHA256/SHA384/SHA512, StrIndex, Substr, Trim, Upper.
UUID functions
UUID4, UUID7.
Window functions
CumeDist, DenseRank, FirstValue, Lag, LastValue, Lead, NthValue, Ntile, PercentRank, Rank, RowNumber.