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DurationField – Django Models

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DurationField is 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. DurationField basically stores a duration, the difference between two dates or times.

Syntax

field_name = models.DurationField(**options)

Django Model DurationField Explanation

Illustration of DurationField using an Example. Consider a project named geeksforgeeks having an app named geeks. 

Refer to the following articles to check how to create a project and an app in Django. 

Enter the following code into models.py file of geeks app.  

Python3




from django.db import models
from django.db.models import Model
# Create your models here.
 
class GeeksModel(Model):
    geeks_field = models.DurationField()


Add the geeks app to INSTALLED_APPS 

Python3




# Application definition
 
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'geeks',
]


Now when we run makemigrations command from the terminal,

Python manage.py makemigrations

A new folder named migrations would be created in geeks directory with a file named 0001_initial.py 

Python3




# Generated by Django 2.2.5 on 2019-09-25 06:00
 
from django.db import migrations, models
 
class Migration(migrations.Migration):
 
    initial = True
 
    dependencies = [
    ]
 
    operations = [
        migrations.CreateModel(
            name ='GeeksModel',
            fields =[
                ('id',
                  models.AutoField(
                  auto_created = True,
                  primary_key = True,
                  serialize = False,
                  verbose_name ='ID'
                )),
                ('geeks_field', models.DurationField()),
            ],
        ),
    ]


Now run, 

Python manage.py migrate

Thus, an geeks_field DurationField is created when you run migrations on the project. It is a field to store datetime.timedelta python object.

How to use DurationField ?

DurationField is used for storing python datetime.timedelta instance in the database. One can store any type of duration based on time or date in the database. To know more about datetime.timedelta, check out Python | datetime.timedelta() function. Let’s try storing a timedelta instance in model created above.

Python3




# importing the model
# from geeks app
from geeks.models import GeeksModel
 
# importing datetime module
import datetime
 
# creating an instance of
# datetime.timedelta
d = datetime.timedelta(days =-1, seconds = 68400)
 
# creating an instance of
# GeeksModel
geek_object = GeeksModel.objects.create(geeks_field = d)
geek_object.save()


Now let’s check it in admin server. We have created an instance of GeeksModel. 

DurationField django models

Field Options

Field Options are the arguments given to each field for applying some constraint or imparting a particular characteristic to a particular Field. For example, adding an argument null = True to DurationField will enable it to store empty values for that table in relational database. 
Here are the field options and attributes that a DurationField can use. 

Field Options Description
Null If True, Django will store empty values as NULL in the database. Default is False.
Blank If True, the field is allowed to be blank. Default is False.
db_column The name of the database column to use for this field. If this isn’t given, Django will use the field’s name. 
 
Default The default value for the field. This can be a value or a callable object. If callable it will be called every time a new object is created. 
 
help_text Extra “help” text to be displayed with the form widget. It’s useful for documentation even if your field isn’t used on a form. 
 
primary_key If True, this field is the primary key for the model.
editable If False, the field will not be displayed in the admin or any other ModelForm. They are also skipped during model validation. Default is True
 
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. 
 
help_text Extra “help” text to be displayed with the form widget. It’s useful for documentation even if your field isn’t used on a form. 
 
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. 
 
validators A list of validators to run for this field. See the validators documentation for more information. 
 
Unique If True, this field must be unique throughout the table. 
 

 



Last Updated : 02 Sep, 2021
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