django.db.models.fields.CharField

class documentation

class CharField(Field):

Known subclasses: django.db.models.fields.CommaSeparatedIntegerField, django.db.models.fields.EmailField, django.db.models.fields.SlugField, django.db.models.fields.URLField

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Undocumented

Method	`__init__`	Undocumented
Method	`_check_db_collation`	Undocumented
Method	`_check_max_length_attribute`	Undocumented
Method	`cast_db_type`	Return the data type to use in the Cast() function.
Method	`check`	Undocumented
Method	`deconstruct`	Return enough information to recreate the field as a 4-tuple:
Method	`formfield`	Return a django.forms.Field instance for this field.
Method	`get_internal_type`	Undocumented
Method	`get_prep_value`	Perform preliminary non-db specific value checks and conversions.
Method	`to_python`	Convert the input value into the expected Python data type, raising django.core.exceptions.ValidationError if the data can't be converted. Return the converted value. Subclasses should override this.
Class Variable	`description`	Undocumented
Instance Variable	`db_collation`	Undocumented

Inherited from Field:

Class Method	`_choices_is_value`	Undocumented
Method	`__copy__`	Undocumented
Method	`__deepcopy__`	Undocumented
Method	`__eq__`	Undocumented
Method	`__hash__`	Undocumented
Method	`__lt__`	Undocumented
Method	`__reduce__`	Pickling should return the model._meta.fields instance of the field, not a new copy of that field. So, use the app registry to load the model and then the field back.
Method	`__repr__`	Display the module, class, and name of the field.
Method	`__str__`	Return "app_label.model_label.field_name" for fields attached to models.
Method	`_check_backend_specific_checks`	Undocumented
Method	`_check_choices`	Undocumented
Method	`_check_db_index`	Undocumented
Method	`_check_deprecation_details`	Undocumented
Method	`_check_field_name`	Check if field name is valid, i.e. 1) does not end with an underscore, 2) does not contain "__" and 3) is not "pk".
Method	`_check_null_allowed_for_primary_keys`	Undocumented
Method	`_check_validators`	Undocumented
Method	`_description`	Undocumented
Method	`_get_flatchoices`	Flattened version of choices tuple.
Method	`clean`	Convert the value's type and run validation. Validation errors from to_python() and validate() are propagated. Return the correct value if no error is raised.
Method	`clone`	Uses deconstruct() to clone a new copy of this Field. Will not preserve any class attachments/attribute names.
Method	`contribute_to_class`	Register the field with the model class it belongs to.
Method	`db_check`	Return the database column check constraint for this field, for the provided connection. Works the same way as db_type() for the case that get_internal_type() does not map to a preexisting model field.
Method	`db_parameters`	Extension of db_type(), providing a range of different return values (type, checks). This will look at db_type(), allowing custom model fields to override it.
Method	`db_type`	Return the database column data type for this field, for the provided connection.
Method	`db_type_parameters`	Undocumented
Method	`db_type_suffix`	Undocumented
Method	`get_attname`	Undocumented
Method	`get_attname_column`	Undocumented
Method	`get_choices`	Return choices with a default blank choices included, for use as <select> choices for this field.
Method	`get_col`	Undocumented
Method	`get_db_converters`	Undocumented
Method	`get_db_prep_save`	Return field's value prepared for saving into a database.
Method	`get_db_prep_value`	Return field's value prepared for interacting with the database backend.
Method	`get_default`	Return the default value for this field.
Method	`get_filter_kwargs_for_object`	Return a dict that when passed as kwargs to self.model.filter(), would yield all instances having the same value for this field as obj has.
Method	`get_pk_value_on_save`	No summary
Method	`has_default`	Return a boolean of whether this field has a default value.
Method	`pre_save`	Return field's value just before saving.
Method	`rel_db_type`	Return the data type that a related field pointing to this field should use. For example, this method is called by ForeignKey and OneToOneField to determine its data type.
Method	`run_validators`	Undocumented
Method	`save_form_data`	Undocumented
Method	`select_format`	Custom format for select clauses. For example, GIS columns need to be selected as AsText(table.col) on MySQL as the table.col data can't be used by Django.
Method	`set_attributes_from_name`	Undocumented
Method	`validate`	Validate value and raise ValidationError if necessary. Subclasses should override this to provide validation logic.
Method	`value_from_object`	Return the value of this field in the given model instance.
Method	`value_to_string`	Return a string value of this field from the passed obj. This is used by the serialization framework.
Class Variable	`auto_creation_counter`	Undocumented
Class Variable	`default_error_messages`	Undocumented
Class Variable	`default_validators`	Undocumented
Class Variable	`empty_strings_allowed`	Undocumented
Class Variable	`empty_values`	Undocumented
Class Variable	`flatchoices`	Undocumented
Class Variable	`hidden`	Undocumented
Class Variable	`many_to_many`	Undocumented
Class Variable	`many_to_one`	Undocumented
Class Variable	`one_to_many`	Undocumented
Class Variable	`one_to_one`	Undocumented
Class Variable	`related_model`	Undocumented
Class Variable	`system_check_deprecated_details`	Undocumented
Class Variable	`system_check_removed_details`	Undocumented
Instance Variable	`_db_tablespace`	Undocumented
Instance Variable	`_error_messages`	Undocumented
Instance Variable	`_unique`	Undocumented
Instance Variable	`_validators`	Undocumented
Instance Variable	`_verbose_name`	Undocumented
Instance Variable	`attname`	Undocumented
Instance Variable	`auto_created`	Undocumented
Instance Variable	`blank`	Undocumented
Instance Variable	`choices`	Undocumented
Instance Variable	`column`	Undocumented
Instance Variable	`concrete`	Undocumented
Instance Variable	`creation_counter`	Undocumented
Instance Variable	`db_column`	Undocumented
Instance Variable	`db_index`	Undocumented
Instance Variable	`default`	Undocumented
Instance Variable	`editable`	Undocumented
Instance Variable	`error_messages`	Undocumented
Instance Variable	`help_text`	Undocumented
Instance Variable	`is_relation`	Undocumented
Instance Variable	`max_length`	Undocumented
Instance Variable	`model`	Undocumented
Instance Variable	`name`	Undocumented
Instance Variable	`null`	Undocumented
Instance Variable	`primary_key`	Undocumented
Instance Variable	`remote_field`	Undocumented
Instance Variable	`serialize`	Undocumented
Instance Variable	`unique_for_date`	Undocumented
Instance Variable	`unique_for_month`	Undocumented
Instance Variable	`unique_for_year`	Undocumented
Instance Variable	`verbose_name`	Undocumented
Property	`_get_default`	Undocumented
Property	`cached_col`	Undocumented
Property	`db_returning`	Private API intended only to be used by Django itself. Currently only the PostgreSQL backend supports returning multiple fields on a model.
Property	`db_tablespace`	Undocumented
Property	`unique`	Undocumented
Property	`validators`	Some validators can't be created at field initialization time. This method provides a way to delay their creation until required.

Inherited from RegisterLookupMixin (via Field):

Class Method	`get_lookups`	Undocumented
Class Method	`register_lookup`	Undocumented
Static Method	`merge_dicts`	Merge dicts in reverse to preference the order of the original list. e.g., merge_dicts([a, b]) will preference the keys in 'a' over those in 'b'.
Class Method	`_clear_cached_lookups`	Undocumented
Class Method	`_get_lookup`	Undocumented
Class Method	`_unregister_lookup`	Remove given lookup from cls lookups. For use in tests only as it's not thread-safe.
Method	`get_lookup`	Undocumented
Method	`get_transform`	Undocumented

def __init__(self, *args, db_collation=None, **kwargs):

overrides django.db.models.fields.Field.__init__

overridden in django.db.models.fields.EmailField, django.db.models.fields.SlugField, django.db.models.fields.URLField

Undocumented

def _check_db_collation(self, databases):

Undocumented

def _check_max_length_attribute(self, **kwargs):

Undocumented

def cast_db_type(self, connection):

overrides django.db.models.fields.Field.cast_db_type

Return the data type to use in the Cast() function.

def check(self, **kwargs):

overrides django.db.models.fields.Field.check

Undocumented

def deconstruct(self):

overrides django.db.models.fields.Field.deconstruct

overridden in django.db.models.fields.EmailField, django.db.models.fields.SlugField, django.db.models.fields.URLField

Return enough information to recreate the field as a 4-tuple:

The name of the field on the model, if contribute_to_class() has been run.

The import path of the field, including the class, e.g. django.db.models.IntegerField. This should be the most portable version, so less specific may be better.

A list of positional arguments.

A dict of keyword arguments.

Note that the positional or keyword arguments must contain values of the following types (including inner values of collection types):

None, bool, str, int, float, complex, set, frozenset, list, tuple, dict

UUID

datetime.datetime (naive), datetime.date

top-level classes, top-level functions - will be referenced by their full import path

Storage instances - these have their own deconstruct() method

This is because the values here must be serialized into a text format (possibly new Python code, possibly JSON) and these are the only types with encoding handlers defined.

There's no need to return the exact way the field was instantiated this time, just ensure that the resulting field is the same - prefer keyword arguments over positional ones, and omit parameters with their default values.

def formfield(self, **kwargs):

overrides django.db.models.fields.Field.formfield

overridden in django.db.models.fields.EmailField, django.db.models.fields.SlugField, django.db.models.fields.URLField

Return a django.forms.Field instance for this field.

def get_internal_type(self):

overrides django.db.models.fields.Field.get_internal_type

overridden in django.db.models.fields.SlugField

Undocumented

def get_prep_value(self, value):

overrides django.db.models.fields.Field.get_prep_value

Perform preliminary non-db specific value checks and conversions.

def to_python(self, value):

overrides django.db.models.fields.Field.to_python

Convert the input value into the expected Python data type, raising django.core.exceptions.ValidationError if the data can't be converted. Return the converted value. Subclasses should override this.

description =

overrides django.db.models.fields.Field.description

overridden in django.db.models.fields.CommaSeparatedIntegerField, django.db.models.fields.EmailField, django.db.models.fields.SlugField, django.db.models.fields.URLField

Undocumented

db_collation =

Undocumented