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Documentation version: 5.0

Acuan bidang model¶

Dokumen ini mengandung semua acuan API dari Field termasuk field options dan field types Django tawarkan.

Lihat juga

Jika bidang-bidang siap-pakai tidak melakukan muslihat, anda dapat mencoba django-localflavor (documentation), yang mengandung bermacam-macam potongan dari kode yang berguna untuk negara dan budaya tertentu.

Juga, anda dapat dengan mudah write your own custom model fields.

Catatan

Secara teknis, model-mdoel ini ditentukan dalam django.db.models.fields, tetapi untuk kenyamanan mereka diimpor kedalam django.db.models; kebiasaan standar adalah menggunakan from django.db import models dan mengacu ke bidang-bidang sebagai models.<Foo>Field.

Pilihan bidang¶

Argumen berikut tersedia pada semua jenis bidang. Semua adalah pilihan.

`null`¶

Field.null¶

Jika True, Django akan menyimpan nilai-nilai kosong sebagai NULL di basisdata. Awalan adalah False.

Hindari menggunakan null pada bidang-bidang berdasarkan-string seperti CharField dan TextField. Jika bidang berdasarkan-string mempunyai null=True, itu berarti mempunyai dua kemungkinan nilai untuk "no data": NULL, dan string kosong. Dalam kebanyakan kasus, itu berulang untuk memiliki dua kemungkinan nilai untuk "no data;" Kebiasaan Django adalah menggunakan string kosong, bukan NULL. Satu pengecualian adalah ketika CharField mempunyai unique=True dan blank=True disetel. Dalam keadaan ini, null=True adalah diwajibkan untuk menghindari pelanggaran batasan unik ketika menyimpan banyak obyek dengan nilai kosong.

Untuk kedua bidang berdasarkan-string dan bukan-berdasarkan-string, anda juga akan butuh mensetel blank=True jika anda berharap mengizinkan nilai kosong dalam formulir, sebagai parameter null hanya mempengaruhi penyimpanan basisdata (lihat blank).

Catatan

Ketika menggunakan backend basisdata Oracle, nilai NULL akan disimpan untuk menyatakan string kosong meskipun dari atribut ini.

`blank`¶

Field.blank¶

Jika True, bidang diizinkan menjadi kosong. Awalan adalah False.

Catat bahwa ini berbeda dari null. null murni hubungan-basisdata, dimana blank adalah hubungan-pengesahan. Jika sebuah bidang mempunyai blank=True, pengesahan formulir akan mengizinkan masukan dari sebuah nilai kosong. Jika sebuah bidang mempunyai blank=False, bidang akan diwajibkan.

Supplying missing values

blank=True can be used with fields having null=False, but this will require implementing clean() on the model in order to programmatically supply any missing values.

`choices`¶

Field.choices¶

A mapping or iterable in the format described below to use as choices for this field. If choices are given, they're enforced by model validation and the default form widget will be a select box with these choices instead of the standard text field.

If a mapping is given, the key element is the actual value to be set on the model, and the second element is the human readable name. For example:

YEAR_IN_SCHOOL_CHOICES = {
    "FR": "Freshman",
    "SO": "Sophomore",
    "JR": "Junior",
    "SR": "Senior",
    "GR": "Graduate",
}

You can also pass a sequence consisting itself of iterables of exactly two items (e.g. [(A1, B1), (A2, B2), …]). The first element in each tuple is the actual value to be set on the model, and the second element is the human-readable name. For example:

YEAR_IN_SCHOOL_CHOICES = [
    ("FR", "Freshman"),
    ("SO", "Sophomore"),
    ("JR", "Junior"),
    ("SR", "Senior"),
    ("GR", "Graduate"),
]

choices can also be defined as a callable that expects no arguments and returns any of the formats described above. For example:

def get_currencies():
    return {i: i for i in settings.CURRENCIES}


class Expense(models.Model):
    amount = models.DecimalField(max_digits=10, decimal_places=2)
    currency = models.CharField(max_length=3, choices=get_currencies)

Passing a callable for choices can be particularly handy when, for example, the choices are:

the result of I/O-bound operations (which could potentially be cached), such as querying a table in the same or an external database, or accessing the choices from a static file.
a list that is mostly stable but could vary from time to time or from project to project. Examples in this category are using third-party apps that provide a well-known inventory of values, such as currencies, countries, languages, time zones, etc.

Changed in Django 5.0:

Support for mappings and callables was added.

Umumnya, itu adalah terbaik menentukan pilihan didalam kelas model, dan menentukan ketetapan bernama-cocok untuk setiap nilai:

from django.db import models


class Student(models.Model):
    FRESHMAN = "FR"
    SOPHOMORE = "SO"
    JUNIOR = "JR"
    SENIOR = "SR"
    GRADUATE = "GR"
    YEAR_IN_SCHOOL_CHOICES = {
        FRESHMAN: "Freshman",
        SOPHOMORE: "Sophomore",
        JUNIOR: "Junior",
        SENIOR: "Senior",
        GRADUATE: "Graduate",
    }
    year_in_school = models.CharField(
        max_length=2,
        choices=YEAR_IN_SCHOOL_CHOICES,
        default=FRESHMAN,
    )

    def is_upperclass(self):
        return self.year_in_school in {self.JUNIOR, self.SENIOR}

Though you can define a choices list outside of a model class and then refer to it, defining the choices and names for each choice inside the model class keeps all of that information with the class that uses it, and helps reference the choices (e.g, Student.SOPHOMORE will work anywhere that the Student model has been imported).

Anda dapat juga mengumpulkan pilihan tersedia anda kedalam kelompok bernama yang dapat digunakan untuk tujuan organisasi:

MEDIA_CHOICES = {
    "Audio": {
        "vinyl": "Vinyl",
        "cd": "CD",
    },
    "Video": {
        "vhs": "VHS Tape",
        "dvd": "DVD",
    },
    "unknown": "Unknown",
}

The key of the mapping is the name to apply to the group and the value is the choices inside that group, consisting of the field value and a human-readable name for an option. Grouped options may be combined with ungrouped options within a single mapping (such as the "unknown" option in this example).

You can also use a sequence, e.g. a list of 2-tuples:

MEDIA_CHOICES = [
    (
        "Audio",
        (
            ("vinyl", "Vinyl"),
            ("cd", "CD"),
        ),
    ),
    (
        "Video",
        (
            ("vhs", "VHS Tape"),
            ("dvd", "DVD"),
        ),
    ),
    ("unknown", "Unknown"),
]

Note that choices can be any sequence object -- not necessarily a list or tuple. This lets you construct choices dynamically. But if you find yourself hacking choices to be dynamic, you're probably better off using a proper database table with a ForeignKey. choices is meant for static data that doesn't change much, if ever.

Catatan

A new migration is created each time the order of choices changes.

For each model field that has choices set, Django will normalize the choices to a list of 2-tuples and add a method to retrieve the human-readable name for the field's current value. See get_FOO_display() in the database API documentation.

meskipun blank=False disetel pada bidang bersama default kemudian sebuah etiket mengandung "---------" akan dibangun dengan kotak pilihan. Untuk menimpa perilaku ini, tambah sebuah tuple pada choices mengandung None; misalnya (None, 'Your String For Display'). Cara lain, anda dapat menggunakan string kosong daripada None dimana ini masuk akal - sseperti pada CharField.

Enumeration types¶

In addition, Django provides enumeration types that you can subclass to define choices in a concise way:

from django.utils.translation import gettext_lazy as _


class Student(models.Model):
    class YearInSchool(models.TextChoices):
        FRESHMAN = "FR", _("Freshman")
        SOPHOMORE = "SO", _("Sophomore")
        JUNIOR = "JR", _("Junior")
        SENIOR = "SR", _("Senior")
        GRADUATE = "GR", _("Graduate")

    year_in_school = models.CharField(
        max_length=2,
        choices=YearInSchool,
        default=YearInSchool.FRESHMAN,
    )

    def is_upperclass(self):
        return self.year_in_school in {
            self.YearInSchool.JUNIOR,
            self.YearInSchool.SENIOR,
        }

These work similar to enum from Python's standard library, but with some modifications:

Enum member values are a tuple of arguments to use when constructing the concrete data type. Django supports adding an extra string value to the end of this tuple to be used as the human-readable name, or label. The label can be a lazy translatable string. Thus, in most cases, the member value will be a (value, label) 2-tuple. See below for an example of subclassing choices using a more complex data type. If a tuple is not provided, or the last item is not a (lazy) string, the label is automatically generated from the member name.
A .label property is added on values, to return the human-readable name.
A number of custom properties are added to the enumeration classes -- .choices, .labels, .values, and .names -- to make it easier to access lists of those separate parts of the enumeration.

Peringatan

These property names cannot be used as member names as they would conflict.
The use of enum.unique() is enforced to ensure that values cannot be defined multiple times. This is unlikely to be expected in choices for a field.

Note that using YearInSchool.SENIOR, YearInSchool['SENIOR'], or YearInSchool('SR') to access or lookup enum members work as expected, as do the .name and .value properties on the members.

If you don't need to have the human-readable names translated, you can have them inferred from the member name (replacing underscores with spaces and using title-case):

>>> class Vehicle(models.TextChoices):
...     CAR = "C"
...     TRUCK = "T"
...     JET_SKI = "J"
...
>>> Vehicle.JET_SKI.label
'Jet Ski'

Since the case where the enum values need to be integers is extremely common, Django provides an IntegerChoices class. For example:

class Card(models.Model):
    class Suit(models.IntegerChoices):
        DIAMOND = 1
        SPADE = 2
        HEART = 3
        CLUB = 4

    suit = models.IntegerField(choices=Suit)

It is also possible to make use of the Enum Functional API with the caveat that labels are automatically generated as highlighted above:

>>> MedalType = models.TextChoices("MedalType", "GOLD SILVER BRONZE")
>>> MedalType.choices
[('GOLD', 'Gold'), ('SILVER', 'Silver'), ('BRONZE', 'Bronze')]
>>> Place = models.IntegerChoices("Place", "FIRST SECOND THIRD")
>>> Place.choices
[(1, 'First'), (2, 'Second'), (3, 'Third')]

If you require support for a concrete data type other than int or str, you can subclass Choices and the required concrete data type, e.g. date for use with DateField:

class MoonLandings(datetime.date, models.Choices):
    APOLLO_11 = 1969, 7, 20, "Apollo 11 (Eagle)"
    APOLLO_12 = 1969, 11, 19, "Apollo 12 (Intrepid)"
    APOLLO_14 = 1971, 2, 5, "Apollo 14 (Antares)"
    APOLLO_15 = 1971, 7, 30, "Apollo 15 (Falcon)"
    APOLLO_16 = 1972, 4, 21, "Apollo 16 (Orion)"
    APOLLO_17 = 1972, 12, 11, "Apollo 17 (Challenger)"

There are some additional caveats to be aware of:

Enumeration types do not support named groups.
Because an enumeration with a concrete data type requires all values to match the type, overriding the blank label cannot be achieved by creating a member with a value of None. Instead, set the __empty__ attribute on the class:
```
class Answer(models.IntegerChoices):
    NO = 0, _("No")
    YES = 1, _("Yes")

    __empty__ = _("(Unknown)")
```

Changed in Django 5.0:

Support for using enumeration types directly in the choices was added.

`db_column`¶

Field.db_column¶

Nama dari kolom basisdata untuk digunakan pada bidang ini. jika tidak diberikan, Django akan menggunakan nama bidang.

Jika nama kolom basisdata anda adalah kata disiapkan SQL, atau mengandung karakter yang tidak diizinkan dalam nama variabel Python -- terutama, tanda penghubung -- itu juga OK. Django mengutip nama kolom dan tabel dinelakang layar.

`db_comment`¶

New in Django 4.2.

Field.db_comment¶

The comment on the database column to use for this field. It is useful for documenting fields for individuals with direct database access who may not be looking at your Django code. For example:

pub_date = models.DateTimeField(
    db_comment="Date and time when the article was published",
)

`db_default`¶

New in Django 5.0.

Field.db_default¶

The database-computed default value for this field. This can be a literal value or a database function, such as Now:

created = models.DateTimeField(db_default=Now())

More complex expressions can be used, as long as they are made from literals and database functions:

month_due = models.DateField(
    db_default=TruncMonth(
        Now() + timedelta(days=90),
        output_field=models.DateField(),
    )
)

Database defaults cannot reference other fields or models. For example, this is invalid:

end = models.IntegerField(db_default=F("start") + 50)

If both db_default and Field.default are set, default will take precedence when creating instances in Python code. db_default will still be set at the database level and will be used when inserting rows outside of the ORM or when adding a new field in a migration.

`db_index`¶

Field.db_index¶

Jika``True``, indeks basisdata akan dibuat untuk bidang ini.

Gunakan pilihan indexes sebagai gantinya.

Where possible, use the Meta.indexes option instead. In nearly all cases, indexes provides more functionality than db_index. db_index may be deprecated in the future.

`db_tablespace`¶

Field.db_tablespace¶

Nama dari database tablespace untuk digunakan untuk indeks bidang ini, jika bidang ini diindeks. Awalan adalah pengaturan DEFAULT_INDEX_TABLESPACE proyek, jika disetel, atau db_tablespace dari model, jika ada. Jika backendtidak mendukung tablespace untuk pengindeksan, pilihan ini diabaikan.

`default`¶

Field.default¶

Nilai awalan untuk bidang. Ini dapat berupa nilai atau obyek callable. Jika callable itu akan dipanggil setiap waktu obyek baru dibuat.

The default can't be a mutable object (model instance, list, set, etc.), as a reference to the same instance of that object would be used as the default value in all new model instances. Instead, wrap the desired default in a callable. For example, if you want to specify a default dict for JSONField, use a function:

def contact_default():
    return {"email": "to1@example.com"}


contact_info = JSONField("ContactInfo", default=contact_default)

lambdas can't be used for field options like default because they can't be serialized by migrations. See that documentation for other caveats.

For fields like ForeignKey that map to model instances, defaults should be the value of the field they reference (pk unless to_field is set) instead of model instances.

The default value is used when new model instances are created and a value isn't provided for the field. When the field is a primary key, the default is also used when the field is set to None.

The default value can also be set at the database level with Field.db_default.

`editable`¶

Field.editable¶

Jika False, bidang tidak ditampilan dalam admin atau ModelForm lain apapun. Mereka juga dilewati selama model validation. Awalan adalah True.

`error_messages`¶

Field.error_messages¶

The error_messages argument lets you override the default messages that the field will raise. Pass in a dictionary with keys matching the error messages you want to override.

Kunci-kunci pesan kesalahan termasuk null, blank, invalid, invalid_choice, unique, dan unique_for_date. Kunci-kunci pesan kesalahan tambahan ditentukan untuk setiap bidang dalam bagian Field types dibawah.

Pesan-pesan kesalahan ini sering tidak menyebarkan ke formulir. Lihat Pertimbangan mengenai error_messages model.

`help_text`¶

Field.help_text¶

Teks "help" tambahan untuk ditampilkan dengan widget formulir. Itu sangat berguna untuk dokumentasi bahkan jika bidang anda tidak digunakan pada formulir.

Note that this value is not HTML-escaped in automatically-generated forms. This lets you include HTML in help_text if you so desire. For example:

help_text = "Please use the following format: <em>YYYY-MM-DD</em>."

Alternatively you can use plain text and django.utils.html.escape() to escape any HTML special characters. Ensure that you escape any help text that may come from untrusted users to avoid a cross-site scripting attack.

`primary_key`¶

Field.primary_key¶

Jika True, bidang ini adalah primary key untuk model.

If you don't specify primary_key=True for any field in your model, Django will automatically add a field to hold the primary key, so you don't need to set primary_key=True on any of your fields unless you want to override the default primary-key behavior. The type of auto-created primary key fields can be specified per app in AppConfig.default_auto_field or globally in the DEFAULT_AUTO_FIELD setting. For more, see Bidang primary key otomatis.

primary_key=True berarti null=False dan unique=True. Hanya satu primary key diizinkan pada sebuah obyek.

The primary key field is read-only. If you change the value of the primary key on an existing object and then save it, a new object will be created alongside the old one.

The primary key field is set to None when deleting an object.

`unik`¶

Field.unique¶

Jika True, bidang ini harus unik diseluruh tabel.

This is enforced at the database level and by model validation. If you try to save a model with a duplicate value in a unique field, a django.db.IntegrityError will be raised by the model's save() method.

Pilihan ini adalah adalah sah pada semua jenis bidang kecuali ManyToManyField dan OneToOneField.

Catat bahwa ketika unique adalah True, anda tidak butuh menentukan db_index, karena unique menyiratkan pembuatan dari sebuah indeks.

`unique_for_date`¶

Field.unique_for_date¶

Setel ini ke nama dari DateField atau DateTimeField untuk membutuhkan dimana bidang ini unik untuk nilai dari bidang tanggal.

For example, if you have a field title that has unique_for_date="pub_date", then Django wouldn't allow the entry of two records with the same title and pub_date.

Note that if you set this to point to a DateTimeField, only the date portion of the field will be considered. Besides, when USE_TZ is True, the check will be performed in the current time zone at the time the object gets saved.

This is enforced by Model.validate_unique() during model validation but not at the database level. If any unique_for_date constraint involves fields that are not part of a ModelForm (for example, if one of the fields is listed in exclude or has editable=False), Model.validate_unique() will skip validation for that particular constraint.

`unique_for_month`¶

Field.unique_for_month¶

Seperti unique_for_date, tetapi membutuhkan bidang unik dengan mematuhi pada bulan.

`unique_for_year`¶

Field.unique_for_year¶

Seperti unique_for_date dan unique_for_month.

`verbose_name`¶

Field.verbose_name¶

A human-readable name for the field. If the verbose name isn't given, Django will automatically create it using the field's attribute name, converting underscores to spaces. See Verbose field names.

`validators`¶

Field.validators¶

Sebuah list dari pengesah untuk berjalan untuk bidang ini. Lihat validators documentation untuk informasi lebih.

Jenis bidang¶

`AutoField`¶

class AutoField(**options)¶

An IntegerField that automatically increments according to available IDs. You usually won't need to use this directly; a primary key field will automatically be added to your model if you don't specify otherwise. See Bidang primary key otomatis.

`BigAutoField`¶

class BigAutoField(**options)¶

Integer 64-bit, seperti AutoField kecuali itu dijamin untuk cocok nomor dari 1 sampai 9223372036854775807.

`BigIntegerField`¶

class BigIntegerField(**options)¶

A 64-bit integer, much like an IntegerField except that it is guaranteed to fit numbers from -9223372036854775808 to 9223372036854775807. The default form widget for this field is a NumberInput.

`BinaryField`¶

class BinaryField(max_length=None, **options)¶

Sebuah bidang untuk menyimpan data binder mentah. Itu dapat diberikan bytes, bytearray, atau memoryview.

Secara awalan, BinaryField menyetel editable menjadi False, dalam kasus itu tidak dapat disertakan dalam ModelForm.

BinaryField.max_length¶: Optional. The maximum length (in bytes) of the field. The maximum length is enforced in Django's validation using MaxLengthValidator.

Menyalahgunakan BinaryField

Meskipun anda mungkin berpikir tentang menyimpan berkas-berkas dalam basisdata, pertimbangkan bahwa itu adalah rancangan buruh dalam 99% dari kasus. Bidang ini bukan sebuah penggantian untuk penangangan static files yang sesuai.

`BooleanField`¶

class BooleanField(**options)¶

Sebuah bidang true/false.

Widget formulir awalan untuk bidang ini adalah CheckboxInput, atau NullBooleanSelect jika null=True.

Nilai awal dari BooleanField adalah None ketika Field.default belum ditentukan.

`CharField`¶

class CharField(max_length=None, **options)¶

Bidang string, untuk string ukuran-kecil- sampai-besar.

Untuk teks besar, gunakan TextField.

Widget formulir awalan untuk bidang ini adalah TextInput.

CharField has the following extra arguments:

CharField.max_length¶: The maximum length (in characters) of the field. The max_length is enforced at the database level and in Django's validation using MaxLengthValidator. It's required for all database backends included with Django except PostgreSQL, which supports unlimited VARCHAR columns.

Catatan

Jika anda sedang menulis sebuah aplikasi yang harus dihubungkan ke banyak backend basisdata, anda harus waspada bahwa ada pembatasan pada max_length untuk beberapa backend. Mengacu pada database backend notes untuk rincian.

Changed in Django 4.2:
Support for unlimited VARCHAR columns was added on PostgreSQL.

CharField.db_collation¶: Optional. The database collation name of the field.

Catatan

Collation names are not standardized. As such, this will not be portable across multiple database backends.

Oracle

Oracle supports collations only when the MAX_STRING_SIZE database initialization parameter is set to EXTENDED.

`DateField`¶

class DateField(auto_now=False, auto_now_add=False, **options)¶

Tanggal, diwakilkan dalam Python oleh instance datetime.date. mempunyai beberapa tambahan, argumen pilihan:

DateField.auto_now¶

Automatically set the field to now every time the object is saved. Useful for "last-modified" timestamps. Note that the current date is always used; it's not just a default value that you can override.

The field is only automatically updated when calling Model.save(). The field isn't updated when making updates to other fields in other ways such as QuerySet.update(), though you can specify a custom value for the field in an update like that.

DateField.auto_now_add¶

Automatically set the field to now when the object is first created. Useful for creation of timestamps. Note that the current date is always used; it's not just a default value that you can override. So even if you set a value for this field when creating the object, it will be ignored. If you want to be able to modify this field, set the following instead of auto_now_add=True:

Untuk DateField: default=date.today - dari datetime.date.today()
Untuk DateTimeField: default=timezone.now - dari django.utils.timezone.now()

The default form widget for this field is a DateInput. The admin adds a JavaScript calendar, and a shortcut for "Today". Includes an additional invalid_date error message key.

Pilihan auto_now_add, auto_now, dan default saling ekslusif. Perpaduan apapun dari pilihan ini akan menghasilkan sebuah kesalahan.

Catatan

Seperti saat ini diterapkan, mengatur auto_now atau auto_now_add menjadi True akan menyebabkan bidang memiliki setelan editable=False dan blank=True.

Catatan

The auto_now and auto_now_add options will always use the date in the default timezone at the moment of creation or update. If you need something different, you may want to consider using your own callable default or overriding save() instead of using auto_now or auto_now_add; or using a DateTimeField instead of a DateField and deciding how to handle the conversion from datetime to date at display time.

`DateTimeField`¶

class DateTimeField(auto_now=False, auto_now_add=False, **options)¶

Sebuah tanggal dan waktu, diwakili dalam Python oleh sebuah contoh datetime.datetime. Mengambil tambahan argumen sama sebagai DateField.

The default form widget for this field is a single DateTimeInput. The admin uses two separate TextInput widgets with JavaScript shortcuts.

`DecimalField`¶

class DecimalField(max_digits=None, decimal_places=None, **options)¶

A fixed-precision decimal number, represented in Python by a Decimal instance. It validates the input using DecimalValidator.

Has the following required arguments:

DecimalField.max_digits¶: Angka maksimal dari bilangan diizinkan dalam angka. Catat bahwa angka ini harus lebih besar dari atau setara pada decimal_places.

DecimalField.decimal_places¶: Sejumlah tempat desiman untuk menyimpan dengan nomor.

For example, to store numbers up to 999.99 with a resolution of 2 decimal places, you'd use:

models.DecimalField(..., max_digits=5, decimal_places=2)

Dan untuk menyimpan angka sampai pada sekitar satu milyar dengan sebuah keputusan dari 10 tempat desimal:

models.DecimalField(..., max_digits=19, decimal_places=10)

Widget formulir awalan untuk bidang ini adalah sebuah NumberInput ketika localize adalah False atau TextInput sebaliknya.

Catatan

For more information about the differences between the FloatField and DecimalField classes, please see FloatField vs. DecimalField. You should also be aware of SQLite limitations of decimal fields.

`DurationField`¶

class DurationField(**options)¶

A field for storing periods of time - modeled in Python by timedelta. When used on PostgreSQL, the data type used is an interval and on Oracle the data type is INTERVAL DAY(9) TO SECOND(6). Otherwise a bigint of microseconds is used.

Catatan

Arithmetic with DurationField works in most cases. However on all databases other than PostgreSQL, comparing the value of a DurationField to arithmetic on DateTimeField instances will not work as expected.

`EmailField`¶

class EmailField(max_length=254, **options)¶

A CharField that checks that the value is a valid email address using EmailValidator.

`FileField`¶

class FileField(upload_to='', storage=None, max_length=100, **options)¶

Sebuah bidang berkas-unggah

Catatan

Argumen primary_key tidak didukung dan akan memunculkan sebuah kesalahan jika digunakan.

Has the following optional arguments:

FileField.upload_to¶

This attribute provides a way of setting the upload directory and file name, and can be set in two ways. In both cases, the value is passed to the Storage.save() method.

If you specify a string value or a Path, it may contain strftime() formatting, which will be replaced by the date/time of the file upload (so that uploaded files don't fill up the given directory). For example:

class MyModel(models.Model):
    # file will be uploaded to MEDIA_ROOT/uploads
    upload = models.FileField(upload_to="uploads/")
    # or...
    # file will be saved to MEDIA_ROOT/uploads/2015/01/30
    upload = models.FileField(upload_to="uploads/%Y/%m/%d/")

If you are using the default FileSystemStorage, the string value will be appended to your MEDIA_ROOT path to form the location on the local filesystem where uploaded files will be stored. If you are using a different storage, check that storage's documentation to see how it handles upload_to.

upload_to mungkin juga dapat dipanggil, seperti sebuah fungsi. Ini akan dipanggil untuk mendapatkan jalur unggahan, termasuk nama berkas. Panggilan iniharus menerima dua argumen dan mengembalikan jalur gaya-Unix (dengan garis miring didepan) untuk dilewatkan bersama ke sistem penyimpanan. Dua argumen adalah:

Argument Deskripsi

Argument	Deskripsi
`instance`	An instance of the model where the `FileField` is defined. More specifically, this is the particular instance where the current file is being attached. Di kebanyakan kasus, obyek ini tidak akan disimpan ke basisdata dulu, jadi jika itu menggunakan `AutoField` awal, itu mungkin belum memiliki nilai untuk bidang primary key nya.
`filename`	The filename that was originally given to the file. This may or may not be taken into account when determining the final destination path.

instance

An instance of the model where the FileField is defined. More specifically, this is the particular instance where the current file is being attached.

Di kebanyakan kasus, obyek ini tidak akan disimpan ke basisdata dulu, jadi jika itu menggunakan AutoField awal, itu mungkin belum memiliki nilai untuk bidang primary key nya.

filename The filename that was originally given to the file. This may or may not be taken into account when determining the final destination path.

Sebagai contoh:

def user_directory_path(instance, filename):
    # file will be uploaded to MEDIA_ROOT/user_<id>/<filename>
    return "user_{0}/{1}".format(instance.user.id, filename)


class MyModel(models.Model):
    upload = models.FileField(upload_to=user_directory_path)

FileField.storage¶: A storage object, or a callable which returns a storage object. This handles the storage and retrieval of your files. See Mengelola berkas for details on how to provide this object.

Widget formulir awalan untuk bidang ini adalah ClearableFileInput.

Menggunakan sebuah FileField atau sebuah ImageField (lihat dibawah) dalam sebuah model mengambil beberapa langkah:

Dalam berkas pengaturan anda, anda butuh menentukan MEDIA_ROOT sebagai jalur penuh ke direktori dimana anda ingin Django menyimpan berkas terunggah. (Untuk penampilan, berkas initidak disimpan di basisdata.) Tentukan MEDIA_URL sebagai URL dasar dari direktori. Pastikan bahwa direktori ini dapat ditulis oleh akun pengguna peladen jaringan.
Tambah FileField or ImageField ke model anda, menentukan pilihan upload_to untuk menentukan subdirectori dari MEDIA_ROOT untuk digunakan pada berkas-berkas terunggah.
All that will be stored in your database is a path to the file (relative to MEDIA_ROOT). You'll most likely want to use the convenience url attribute provided by Django. For example, if your ImageField is called mug_shot, you can get the absolute path to your image in a template with {{ object.mug_shot.url }}.

For example, say your MEDIA_ROOT is set to '/home/media', and upload_to is set to 'photos/%Y/%m/%d'. The '%Y/%m/%d' part of upload_to is strftime() formatting; '%Y' is the four-digit year, '%m' is the two-digit month and '%d' is the two-digit day. If you upload a file on Jan. 15, 2007, it will be saved in the directory /home/media/photos/2007/01/15.

If you wanted to retrieve the uploaded file's on-disk filename, or the file's size, you could use the name and size attributes respectively; for more information on the available attributes and methods, see the File class reference and the Mengelola berkas topic guide.

Catatan

Berkas disimpan sebagai bagian dari menyimpan model dalam basisdata, jadi berkas nama sebenarnya digunakan pada cakram tidak dapat bergantung setelah model disimpan.

The uploaded file's relative URL can be obtained using the url attribute. Internally, this calls the url() method of the underlying Storage class.

Note that whenever you deal with uploaded files, you should pay close attention to where you're uploading them and what type of files they are, to avoid security holes. Validate all uploaded files so that you're sure the files are what you think they are. For example, if you blindly let somebody upload files, without validation, to a directory that's within your web server's document root, then somebody could upload a CGI or PHP script and execute that script by visiting its URL on your site. Don't allow that.

Also note that even an uploaded HTML file, since it can be executed by the browser (though not by the server), can pose security threats that are equivalent to XSS or CSRF attacks.

FileField instances are created in your database as varchar columns with a default max length of 100 characters. As with other fields, you can change the maximum length using the max_length argument.

`FileField` dan `FieldFile`¶

class FieldFile¶

Ketika anda mengakses FileField pada model, anda diberikan sebah contoh dari FieldFile sebagai sebuah proxy untuk mengakses berkas pokok.

The API of FieldFile mirrors that of File, with one key difference: The object wrapped by the class is not necessarily a wrapper around Python's built-in file object. Instead, it is a wrapper around the result of the Storage.open() method, which may be a File object, or it may be a custom storage's implementation of the File API.

In addition to the API inherited from File such as read() and write(), FieldFile includes several methods that can be used to interact with the underlying file:

Peringatan

Dua metode dari kelas ini, save() dan delete(), awalan pada menyimpan obyek model dari FieldFile terkait dalam basisdata.

FieldFile.name¶

Nama dari berkas termasuk jalur relatif dari akar dari Storage dari FileField terkait.

FieldFile.path¶

A read-only property to access the file's local filesystem path by calling the path() method of the underlying Storage class.

FieldFile.size¶

Hasil dari metode pokok Storage.size().

FieldFile.url¶

A read-only property to access the file's relative URL by calling the url() method of the underlying Storage class.

FieldFile.open(mode='rb')¶

Opens or reopens the file associated with this instance in the specified mode. Unlike the standard Python open() method, it doesn't return a file descriptor.

Since the underlying file is opened implicitly when accessing it, it may be unnecessary to call this method except to reset the pointer to the underlying file or to change the mode.

FieldFile.close()¶

Berperilaku seperti metode file.close() Python standar dan menutup berkas berkaitan dengan contoh ini.

FieldFile.save(name, content, save=True)¶

This method takes a filename and file contents and passes them to the storage class for the field, then associates the stored file with the model field. If you want to manually associate file data with FileField instances on your model, the save() method is used to persist that file data.

Takes two required arguments: name which is the name of the file, and content which is an object containing the file's contents. The optional save argument controls whether or not the model instance is saved after the file associated with this field has been altered. Defaults to True.

Note that the content argument should be an instance of django.core.files.File, not Python's built-in file object. You can construct a File from an existing Python file object like this:

from django.core.files import File

# Open an existing file using Python's built-in open()
f = open("/path/to/hello.world")
myfile = File(f)

Atau anda dapat membangun satu dari sebush string Python seperti ini:

from django.core.files.base import ContentFile

myfile = ContentFile("hello world")

Untuk informasi lebih, lihat Mengelola berkas.

FieldFile.delete(save=True)¶

Deletes the file associated with this instance and clears all attributes on the field. Note: This method will close the file if it happens to be open when delete() is called.

The optional save argument controls whether or not the model instance is saved after the file associated with this field has been deleted. Defaults to True.

Note that when a model is deleted, related files are not deleted. If you need to cleanup orphaned files, you'll need to handle it yourself (for instance, with a custom management command that can be run manually or scheduled to run periodically via e.g. cron).

`FilePathField`¶

class FilePathField(path='', match=None, recursive=False, allow_files=True, allow_folders=False, max_length=100, **options)¶

A CharField whose choices are limited to the filenames in a certain directory on the filesystem. Has some special arguments, of which the first is required:

FilePathField.path¶

Required. The absolute filesystem path to a directory from which this FilePathField should get its choices. Example: "/home/images".

path may also be a callable, such as a function to dynamically set the path at runtime. Example:

import os
from django.conf import settings
from django.db import models


def images_path():
    return os.path.join(settings.LOCAL_FILE_DIR, "images")


class MyModel(models.Model):
    file = models.FilePathField(path=images_path)

FilePathField.match¶: Optional. A regular expression, as a string, that FilePathField will use to filter filenames. Note that the regex will be applied to the base filename, not the full path. Example: "foo.*\.txt$", which will match a file called foo23.txt but not bar.txt or foo23.png.

FilePathField.recursive¶: Optional. Either True or False. Default is False. Specifies whether all subdirectories of path should be included

FilePathField.allow_files¶: Optional. Either True or False. Default is True. Specifies whether files in the specified location should be included. Either this or allow_folders must be True.

FilePathField.allow_folders¶: Optional. Either True or False. Default is False. Specifies whether folders in the specified location should be included. Either this or allow_files must be True.

The one potential gotcha is that match applies to the base filename, not the full path. So, this example:

FilePathField(path="/home/images", match="foo.*", recursive=True)

...will match /home/images/foo.png but not /home/images/foo/bar.png because the match applies to the base filename (foo.png and bar.png).

FilePathField instances are created in your database as varchar columns with a default max length of 100 characters. As with other fields, you can change the maximum length using the max_length argument.

`FloatField`¶

class FloatField(**options)¶

Angka floating-point diwakilkan oleh Python oleh instance float.

Widget formulir awalan untuk bidang ini adalah sebuah NumberInput ketika localize adalah False atau TextInput sebaliknya.

FloatField vs. DecimalField

The FloatField class is sometimes mixed up with the DecimalField class. Although they both represent real numbers, they represent those numbers differently. FloatField uses Python's float type internally, while DecimalField uses Python's Decimal type. For information on the difference between the two, see Python's documentation for the decimal module.

`GeneratedField`¶

New in Django 5.0.

class GeneratedField(expression, output_field, db_persist=None, **kwargs)¶

A field that is always computed based on other fields in the model. This field is managed and updated by the database itself. Uses the GENERATED ALWAYS SQL syntax.

There are two kinds of generated columns: stored and virtual. A stored generated column is computed when it is written (inserted or updated) and occupies storage as if it were a regular column. A virtual generated column occupies no storage and is computed when it is read. Thus, a virtual generated column is similar to a view and a stored generated column is similar to a materialized view.

GeneratedField.expression¶

An Expression used by the database to automatically set the field value each time the model is changed.

The expressions should be deterministic and only reference fields within the model (in the same database table). Generated fields cannot reference other generated fields. Database backends can impose further restrictions.

GeneratedField.output_field¶: A model field instance to define the field's data type.

GeneratedField.db_persist¶

Determines if the database column should occupy storage as if it were a real column. If False, the column acts as a virtual column and does not occupy database storage space.

PostgreSQL only supports persisted columns. Oracle only supports virtual columns.

Refresh the data

Since the database always computed the value, the object must be reloaded to access the new value after save(), for example, by using refresh_from_db().

Database limitations

There are many database-specific restrictions on generated fields that Django doesn't validate and the database may raise an error e.g. PostgreSQL requires functions and operators referenced in a generated column to be marked as IMMUTABLE.

You should always check that expression is supported on your database. Check out MariaDB, MySQL, Oracle, PostgreSQL, or SQLite docs.

`GenericIPAddressField`¶

class GenericIPAddressField(protocol='both', unpack_ipv4=False, **options)¶

An IPv4 or IPv6 address, in string format (e.g. 192.0.2.30 or 2a02:42fe::4). The default form widget for this field is a TextInput.

Normalisasi alamat IPv6 mengikuti RFC 4291#section-2.2 bagian 2.2, termasuk menggunakan bentuk IPv4 disarankan dalam paragraf 3 dari bagian itu, seperti ::ffff:192.0.2.0. Sebagai contoh, 2001:0::0:01 akan dinormalkan menjadi 2001::1, dan ::ffff:0a0a:0a0a menjadi ::ffff:10.10.10.10. Semau karakter dirubah menjadi huruf kecil.

GenericIPAddressField.protocol¶: Limits valid inputs to the specified protocol. Accepted values are 'both' (default), 'IPv4' or 'IPv6'. Matching is case insensitive.

GenericIPAddressField.unpack_ipv4¶: Unpacks IPv4 mapped addresses like ::ffff:192.0.2.1. If this option is enabled that address would be unpacked to 192.0.2.1. Default is disabled. Can only be used when protocol is set to 'both'.

Jika anda mengizinkan nilai kosong, anda harus mengizinkan nilai null karena nilai kosong disimpan sebagai null.

`ImageField`¶

class ImageField(upload_to=None, height_field=None, width_field=None, max_length=100, **options)¶

Inherits all attributes and methods from FileField, but also validates that the uploaded object is a valid image.

In addition to the special attributes that are available for FileField, an ImageField also has height and width attributes.

To facilitate querying on those attributes, ImageField has the following optional arguments:

ImageField.height_field¶: Name of a model field which will be auto-populated with the height of the image each time the model instance is saved.

ImageField.width_field¶: Name of a model field which will be auto-populated with the width of the image each time the model instance is saved.

Membutuhkan pustaka Pillow

ImageField instances are created in your database as varchar columns with a default max length of 100 characters. As with other fields, you can change the maximum length using the max_length argument.

Widget formulir awalan untuk bidang ini adalah ClearableFileInput.

`IntegerField`¶

class IntegerField(**options)¶

Sebuah integer. Nilai dari -2147483648 sampai 2147483647 aman dalam semua basisdata didukung oleh Django.

Itu menggunakan MinValueValidator dan MaxValueValidator untuk mensahkan masukan berdasarkan pada nilai yang didukung basisdata awalan.

Widget formulir awalan untuk bidang ini adalah sebuah NumberInput ketika localize adalah False atau TextInput sebaliknya.

`JSONField`¶

class JSONField(encoder=None, decoder=None, **options)¶

Sebuah bidang untuk menyimpan data tersandi JSON. Dalam Python data diwakili dalam bentuk asli Python nya: dictionary, string, angka, booelan dan None.

JSONField is supported on MariaDB, MySQL, Oracle, PostgreSQL, and SQLite (with the JSON1 extension enabled).

JSONField.encoder¶

An optional json.JSONEncoder subclass to serialize data types not supported by the standard JSON serializer (e.g. datetime.datetime or UUID). For example, you can use the DjangoJSONEncoder class.

Awalan untuk json.JSONEncoder.

JSONField.decoder¶

An optional json.JSONDecoder subclass to deserialize the value retrieved from the database. The value will be in the format chosen by the custom encoder (most often a string). Your deserialization may need to account for the fact that you can't be certain of the input type. For example, you run the risk of returning a datetime that was actually a string that just happened to be in the same format chosen for datetimes.

Awalan untuk json.JSONDecoder.

To query JSONField in the database, see Meminta JSONField.

Default value

If you give the field a default, ensure it's a callable such as the dict class or a function that returns a fresh object each time. Incorrectly using a mutable object like default={} or default=[] creates a mutable default that is shared between all instances.

Indexing

Index and Field.db_index both create a B-tree index, which isn't particularly helpful when querying JSONField. On PostgreSQL only, you can use GinIndex that is better suited.

Pengguna PostgreSQL

PostgreSQL mempunyai dua jenis data berdasarkan JSON asli: json dan jsonb. Perbedaan utama diantara mereka adalah bagaimana mereka disimpan dan bagaimana mereka dapat diminta. Bidang json PostgreSQL disimpan sebagai perwakilan string asli dari JSON dan harus disandikan dengan cepat ketika permintaan berdasarkan pada kunci-kunci. Bidang jsonb disimpan berdasarkan pada struktur sebenarnya dari JSON yang mengizinkan pengindeksan. Pertukaran adalah tambahan biaya kecil pada menulis ke bidang jsonb field. JSONField menggunakan jsonb.

Pengguna Oracle

Oracle Database does not support storing JSON scalar values. Only JSON objects and arrays (represented in Python using dict and list) are supported.

`PositiveBigIntegerField`¶

class PositiveBigIntegerField(**options)¶

Like a PositiveIntegerField, but only allows values under a certain (database-dependent) point. Values from 0 to 9223372036854775807 are safe in all databases supported by Django.

`PositiveIntegerField`¶

class PositiveIntegerField(**options)¶

Like an IntegerField, but must be either positive or zero (0). Values from 0 to 2147483647 are safe in all databases supported by Django. The value 0 is accepted for backward compatibility reasons.

`PositiveSmallIntegerField`¶

class PositiveSmallIntegerField(**options)¶

Like a PositiveIntegerField, but only allows values under a certain (database-dependent) point. Values from 0 to 32767 are safe in all databases supported by Django.

`SlugField`¶

class SlugField(max_length=50, **options)¶

Slug is a newspaper term. A slug is a short label for something, containing only letters, numbers, underscores or hyphens. They're generally used in URLs.

Like a CharField, you can specify max_length (read the note about database portability and max_length in that section, too). If max_length is not specified, Django will use a default length of 50.

menunjuk pengaturan Field.db_index ke True.

Itu sering berguna untuk otomatis mengisi dimuka sebuah SlugField berdasarkan pada nilai dari beberapa nilai lain. Anda dapat melakukan ini otomatis di admin menggunakan prepopulated_fields.

Itu menggunakan validate_slug atau validate_unicode_slug for validation.

SlugField.allow_unicode¶: Jika True, bidang menerima huruf Unicode ebagai tambahan pada huruf ASCII. Awalan menjadi False.

`SmallAutoField`¶

class SmallAutoField(**options)¶

Like an AutoField, but only allows values under a certain (database-dependent) limit. Values from 1 to 32767 are safe in all databases supported by Django.

`SmallIntegerField`¶

class SmallIntegerField(**options)¶

Like an IntegerField, but only allows values under a certain (database-dependent) point. Values from -32768 to 32767 are safe in all databases supported by Django.

`TextField`¶

class TextField(**options)¶

A large text field. The default form widget for this field is a Textarea.

Jika anda menentukan atribut max_length, itu akan dipantulkan di widget Textarea dari bidang formulir dibangkitkan-otomatis. Bagaimanapun itu tidak dipaksa pada model atau tingkatan basisdata. Gunakan CharField untuk itu.

TextField.db_collation¶: Optional. The database collation name of the field.

Catatan

Collation names are not standardized. As such, this will not be portable across multiple database backends.

Oracle

Oracle does not support collations for a TextField.

`TimeField`¶

class TimeField(auto_now=False, auto_now_add=False, **options)¶

A time, represented in Python by a datetime.time instance. Accepts the same auto-population options as DateField.

The default form widget for this field is a TimeInput. The admin adds some JavaScript shortcuts.

`URLField`¶

class URLField(max_length=200, **options)¶

Sebuah CharField untuk URL, disahkan oleh URLValidator.

The default form widget for this field is a URLInput.

Seperti semua CharField subclasses, URLField mengambil pilihan argumen max_length. Jika anda tidak menentukan max_length, sebuah awalan 200 digunakan.

`UUIDField`¶

class UUIDField(**options)¶

A field for storing universally unique identifiers. Uses Python's UUID class. When used on PostgreSQL and MariaDB 10.7+, this stores in a uuid datatype, otherwise in a char(32).

Universally unique identifiers are a good alternative to AutoField for primary_key. The database will not generate the UUID for you, so it is recommended to use default:

import uuid
from django.db import models


class MyUUIDModel(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    # other fields

Catata bahwa sebuah callable (dengan tanda kurung dihapus) dilewatkan pada default, bukan sebuah instance dari UUID.

Lookups on PostgreSQL and MariaDB 10.7+

Using iexact, contains, icontains, startswith, istartswith, endswith, or iendswith lookups on PostgreSQL don't work for values without hyphens, because PostgreSQL and MariaDB 10.7+ store them in a hyphenated uuid datatype type.

Acuan API Bidang¶

class Field¶

Field is an abstract class that represents a database table column. Django uses fields to create the database table (db_type()), to map Python types to database (get_prep_value()) and vice-versa (from_db_value()).

A field is thus a fundamental piece in different Django APIs, notably, models and querysets.

In models, a field is instantiated as a class attribute and represents a particular table column, see Model. It has attributes such as null and unique, and methods that Django uses to map the field value to database-specific values.

Sebuah Field adalah subkelas dari RegisterLookupMixin dan dengan demikian kedua Transform dan Lookup dapat didaftarkan pada itu untuk digunakan dalam (misalnya field_name__exact="foo") QuerySet. Semua built-in lookups didaftarkan secara awalan.

All of Django's built-in fields, such as CharField, are particular implementations of Field. If you need a custom field, you can either subclass any of the built-in fields or write a Field from scratch. In either case, see Bagaimana membuat bidang model disesuaikan.

description¶

Gambaran bertele-tele dari bidang, misalnya aplikasi django.contrib.admindocs.

Gambaran dapat berupa dari bentuk

description = _("String (up to %(max_length)s)")

dimana argumen-argumen ditambahkan dari __dict__ bidang-bidang.

descriptor_class¶: A class implementing the descriptor protocol that is instantiated and assigned to the model instance attribute. The constructor must accept a single argument, the Field instance. Overriding this class attribute allows for customizing the get and set behavior.

Untuk memetakan sebuah Field pada jenis khusus-basisdata, Django membuka beberapa metode-metode:

get_internal_type()¶

Mengembalikan sebuah string menamakan bidang ini untuk tujuan khusus backend. Secara awalan, itu mengembalikan nama kelas.

Lihat Menyamai jenis bidang siap pakai untuk penggunaan dalam bidang penyesuaian.

db_type(connection)¶

Mengembalikan jenis data kolom basisdata untuk Field, dimasukkan kedalam akun connection.

Lihat Jenis basisdata penyesuaian untuk penggunaan dalam bidang penyesuaian.

rel_db_type(connection)¶

Returns the database column data type for fields such as ForeignKey and OneToOneField that point to the Field, taking into account the connection.

Lihat Jenis basisdata penyesuaian untuk penggunaan dalam bidang penyesuaian.

Ada tiga keadaan utama dimana Django butuh berinteraksi dengan backend basisdata dan bidang-bidang:

ketika itu meminta basisdata (nilai Python -> nilai backend basisdata)
ketika itu memuat data dari basisdata (nilai backend basisdata -> nilai Python)
ketika itu menyimpan ke basisdata (nilai Python -> nilai backend basisdata)

Ketika meminta, get_db_prep_value() dan get_prep_value() digunakan:

get_prep_value(value)¶

value adalah nilai saat ini dari atribut model, dan metode harus mengembalikan data dalam bentuk yang telah dipersiapkan untuk digunakan sebagai sebuah parameter dalam sebuah permintaan.

Lihat Mengubah obyek Python ke nilai pencarian untuk penggunaan.

get_db_prep_value(value, connection, prepared=False)¶

Merubah value pada nilai khusus-backend. Secara awalan itu mengembalikan value jika prepared=True dan get_prep_value() jika adalah False.

Lihat Mengubah nilai pencarian ke nilai basisdata untuk penggunaan.

Ketika memuat data, from_db_value() digunakan:

from_db_value(value, expression, connection)¶

Merubah nilai ketika dikembalikan oleh basisdata ke obyek Python. Itu adalah balikan dari get_prep_value().

Metode ini tidak digunakan untuk kebanyakan bidang-bidang siap-pakai ketika backend basisdata sudah mengembalikan jenis Python yang benar, atau backend itu sendiri melakukan perubahan.

expression is the same as self.

Lihat Mengubah nilai menjadi obyek Python untuk penggunaan.

Catatan

Untuk alasan penampilan, from_db_value tidak diterapkan sebagai sebuah no-op pada bidang-bidang yang tidak membutuhkan itu (semua bidang-bidang Django). Karena itu anda mungkin tidak memanggil super dalam penentuan anda.

Ketika menyimpan, pre_save() dan get_db_prep_save() digunakan:

get_db_prep_save(value, connection)¶: Same as the get_db_prep_value(), but called when the field value must be saved to the database. By default returns get_db_prep_value().

pre_save(model_instance, add)¶

Method called prior to get_db_prep_save() to prepare the value before being saved (e.g. for DateField.auto_now).

model_instance is the instance this field belongs to and add is whether the instance is being saved to the database for the first time.

It should return the value of the appropriate attribute from model_instance for this field. The attribute name is in self.attname (this is set up by Field).

Lihat Mengolah nilai sebelum menyimpan untuk penggunaan.

Fields often receive their values as a different type, either from serialization or from forms.

to_python(value)¶

Converts the value into the correct Python object. It acts as the reverse of value_to_string(), and is also called in clean().

Lihat Mengubah nilai menjadi obyek Python untuk penggunaan.

Besides saving to the database, the field also needs to know how to serialize its value:

value_from_object(obj)¶

Returns the field's value for the given model instance.

Metode ini sering digunakan oleh value_to_string().

value_to_string(obj)¶

Merubah obj menjadi sebuah string. Digunakan untuk menserialisasikan nilai dari bidang.

Lihat Mengubah data field untuk serialisasi untuk penggunaan.

Ketika menggunakan model forms, Field butuh mengetahui bidang formulir mana itu harus diwakili:

formfield(form_class=None, choices_form_class=None, **kwargs)¶

Mengembalikan django.forms.Field awalan dari bidang ini untuk ModelForm.

Secara awalan, jika kedua form_class dan choices_form_class adalah None, itu menggunakan CharField. Jika bidang mempunyai choices dan choices_form_class tidak ditentukan, itu menggunakan TypedChoiceField.

Lihat Menentukan bidang formulir untuk sebuah bidang model untuk penggunaan.

deconstruct()¶

Mengembalikan 4-tuple dengan informasi cukup untuk membuat kembali bidang:

Nama dari bidang pada model.
Jalur impor dari bidang (misalnya "django.db.models.IntegerField"). Ini harus versi paling ringan, jadi kurang spesifik mungkin lebih baik.
Daftar dari argumen penempatan.
Sebuah dict dari argumen kata kunci.

Metode ini harus ditambahkan pada bidang sebekum 1.7 untuk memindahkan datanya menggunakan Perpindahan.

Pencarian pendaftaran dan pengambilan¶

Field implements the lookup registration API. The API can be used to customize which lookups are available for a field class and its instances, and how lookups are fetched from a field.

Changed in Django 4.2:

Support for registering lookups on Field instances was added.

Acuan atribut bidang¶

Every Field instance contains several attributes that allow introspecting its behavior. Use these attributes instead of isinstance checks when you need to write code that depends on a field's functionality. These attributes can be used together with the Model._meta API to narrow down a search for specific field types. Custom model fields should implement these flags.

Atribut untuk bidang¶

Field.auto_created¶: Bendera Boolean yang menunjukkan jika bidang otomatis dibuat, seperti OneToOneField digunakan oleh warisan model.

Field.concrete¶: Bendera Boolean mengindikasikan jika bidang mempunyai kolom terkait dengan itu.

Field.hidden¶: Boolean flag that indicates if a field is hidden and should not be returned by Options.get_fields() by default. An example is the reverse field for a ForeignKey with a related_name that starts with '+'.

Field.is_relation¶: Bendera Boolean yang menunjukkan jika sebuah bidang mengandung acuan ke satu atau lebih model untuk kegunaannya (misalnya ForeignKey, ManyToManyField, OneToOneField, dll.).

Field.model¶: Returns the model on which the field is defined. If a field is defined on a superclass of a model, model will refer to the superclass, not the class of the instance.

Atribut untuk bidang dengan hubungan¶

These attributes are used to query for the cardinality and other details of a relation. These attribute are present on all fields; however, they will only have boolean values (rather than None) if the field is a relation type (Field.is_relation=True).

Field.many_to_many¶: Bendera Boolean adalah True jika bidang mempunyai hubungan many-to-many; False sebaliknya. Hanya bidang disertakan dengan Django dimana ini adalah True adalah ManyToManyField.

Field.many_to_one¶: Bendera Boolean adalah True jika bidang mempunyai hubungan many-to-one, seperti ForeignKey; False sebaliknya.

Field.one_to_many¶: Bendera Boolean adalah True jika bidang mempunyai hubungan one-to-many, seperti GenericRelation atau kebalikan dari ForeignKey; False sebaliknya.

Field.one_to_one¶: Bendera Boolean adalah True jika bidang mempunyai hubungan one-to-one, seperti OneToOneField; False sebaliknya.

Field.related_model¶: Points to the model the field relates to. For example, Author in ForeignKey(Author, on_delete=models.CASCADE). The related_model for a GenericForeignKey is always None.

Model

Acuan index model

Dokumentasi

Acuan bidang model¶

Pilihan bidang¶

null¶

blank¶

choices¶

Enumeration types¶

db_column¶

db_comment¶

db_default¶

db_index¶

db_tablespace¶

default¶

editable¶

error_messages¶

help_text¶

primary_key¶

unik¶

unique_for_date¶

unique_for_month¶

unique_for_year¶

verbose_name¶

validators¶

Jenis bidang¶

AutoField¶

BigAutoField¶

BigIntegerField¶

BinaryField¶

BooleanField¶

CharField¶

DateField¶

DateTimeField¶

DecimalField¶

DurationField¶

EmailField¶

FileField¶

FileField dan FieldFile¶

FilePathField¶

FloatField¶

GeneratedField¶

GenericIPAddressField¶

ImageField¶

IntegerField¶

JSONField¶

PositiveBigIntegerField¶

PositiveIntegerField¶

PositiveSmallIntegerField¶

SlugField¶

SmallAutoField¶

SmallIntegerField¶

TextField¶

TimeField¶

URLField¶

UUIDField¶

Bidang hubungan¶

ForeignKey¶

Perwakilan Basisdata¶

Penjelasan¶

ManyToManyField¶

Perwakilan Basisdata¶

Penjelasan¶

OneToOneField¶

Acuan API Bidang¶

Pencarian pendaftaran dan pengambilan¶

Acuan atribut bidang¶

Atribut untuk bidang¶

Atribut untuk bidang dengan hubungan¶

Additional Information

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`null`¶

`blank`¶

`choices`¶

`db_column`¶

`db_comment`¶

`db_default`¶

`db_index`¶

`db_tablespace`¶

`default`¶

`editable`¶

`error_messages`¶

`help_text`¶

`primary_key`¶

`unik`¶

`unique_for_date`¶

`unique_for_month`¶

`unique_for_year`¶

`verbose_name`¶

`validators`¶

`AutoField`¶

`BigAutoField`¶

`BigIntegerField`¶

`BinaryField`¶

`BooleanField`¶

`CharField`¶

`DateField`¶

`DateTimeField`¶

`DecimalField`¶

`DurationField`¶

`EmailField`¶

`FileField`¶

`FileField` dan `FieldFile`¶

`FilePathField`¶

`FloatField`¶

`GeneratedField`¶

`GenericIPAddressField`¶

`ImageField`¶

`IntegerField`¶

`JSONField`¶

`PositiveBigIntegerField`¶

`PositiveIntegerField`¶

`PositiveSmallIntegerField`¶

`SlugField`¶

`SmallAutoField`¶

`SmallIntegerField`¶

`TextField`¶

`TimeField`¶

`URLField`¶

`UUIDField`¶

`ForeignKey`¶

`ManyToManyField`¶

`OneToOneField`¶