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Using Django Form Fields, Widgets, and Attributes

Explain verbose_name and verbose_name_plural in Django

Excerpt from the above:

In this article, we explain verbose_name and verbose_name_plural in Django.
So both verbose_name and verbose_name_plural are ways of making objects human readable or converting to a point where they are human readable.
A notable place where verbose_name and verbose_name_plural can apply to is objects in a database table.
In Python, all rows of data in a database table are objects.
In Python, pretty much almost everything is an object, including strings, integers, and so on.
In this example, we deal with objects of a database table (i.e., the rows of data entered into the database table).
Let’s just go over an example, because this is probably the best way to learn this.
So let’s say we have the following code below to create a database table.

from django.db import models
 
class Child(models.Model):
    name= models.CharField(
        max_length=100,
        verbose_name="Child's First Name and Last Name"
    )
    weight= models.DecimalField(max_digits=3, decimal_places=2)
 
    def __str__(self):
        return self.name
 


We’ll now go over the code.
So, like any database table creation, we import models from django.db
We create a database table called Child.
In this Child database table, we have a name field and a weight field (the weight field is of type DecimalField and can have up to 3 digits and precision of 2 decimal places).
The name field is where we make use of the verbose_name attribute. What verbose_name does is it adds a label to the side of a database field. It works very much like label for forms in Django. verbose_name is pretty much the equivalent of the label attribute for forms. verbose_name is what is used to give labels to forms.
You would use verbose_name if you don’t want the default database field name (in this case, name) to be shown. Django automatically capitalizes a field name, so ‘Name’ would be displayed. But this could cause ambiguity. A person may not know it’s the full name we want. They may think just the first name or just the last name. Therefore, we can use verbose_name and explicity tell the user, ‘Child’s First Name and Last Name’. This cuts out any ambiguity that may possibly exist.
verbose_name, in my opinion, is a very appropriate name. The verbose_name specified is normally more verbose so that you can explicitly tell a user what to add. Instead of just ‘Name’ being displayed, we now display, ‘Child’s First Name and Last Name’.
So this is one of the uses of verbose_name.
It allows us to explicity state instructions next to a database table field.
We then define a __str__ method so that if we retrieve an object, the name is returned instead of just generic non-human readable text.

Now let’s go back to the same example we had before with the Child database table.
If you’re somewhat familiar with database tables in Django, you know that the table name should be declared to be a singular form, because in the admin page of Django, it ends with pluralizing the table name. This is because a table is really a representation of objects. So if you declare name such as Comment, it really is a collection of Comments (so Django automatically pluralizes it in the admin page once the database table is created and registered).
By default, Django adds a ‘s’ to a table name in the admin page.
However, this doesn’t always work. For example, if a database table called ‘Child’, the plural of ‘Child’ is really ‘Children’, not ‘Childs’.
If you create a database table called ‘Child’ and register it in the admin.py file and go to the admin page, you’ll see ‘Childs’.
So there is a way in Django, you can explicitly declare what the singular form of the database objects should be and what the plural form of the database objects should be. And this can be done by using verbose_name and verbose_name_plural attributes.
So, in the code below, we explicitly declare the singular form of each of the objects of the Child database table to be ‘Child’ and the plural form of the objects to be ‘Children’.

from django.db import models
 
class Child(models.Model):
    name= models.CharField(
        max_length=100,
        verbose_name="Child's First Name and Last Name"
    )
    weight= models.DecimalField(max_digits=3, decimal_places=2)
 
    class Meta:
        verbose_name = 'Child'
        verbose_name_plural = 'Children'
 
    def __str__(self):
        return self.name
 

So we have the same file as before, but just with a class Meta added.
What a class Meta is, if you’re familiar with HTML, meta is just data about something, a web page, or a database table. It doesn’t alter the function of the item, it just tells about the data. In HTML, the keywords and description content in the head tag is meta data. It just tells us about the page. In Django, we use meta data about a database table to tell Django things about the database table. In this example, we specify that the singular form of the object of the database table should be ‘Child’ and the plural form of the database table should be ‘Children’
And now you register the database table in admin.py using the line, admin.site.register(Child), (make sure you imported the database table from the models.py file into to the admin.py file), you will now see the plural form of the objects of the database table. And if you click in the database table, you will see the singular form.
And this is pretty good uses and good knowledge to know that you can use verbose_name and verbose_name_plural to specify meta data about a database table in Django.