Django Models

A Django model is a table in your database.

Up until now in this tutorial, output has been static data from Python or HTML templates. Now we will see how Django allows us to work with data, without having to change or upload files in the process. In Django, data is created in objects, called Models, and is actually tables in a database. Create Table (Model) To create a model, navigate to the models.py file in the /members/ folder. Open it, and add a

Member class, and describe the table fields in it:

from django.db import models

class Member(models.Model):

The first field, firstname, is a Text field, and will contain the first name of the members. The second field, lastname, is also a Text field, with the member's last name. Both firstname and lastname is set up to have a maximum of 255 characters.

When we created the Django project, we got an empty SQLite database. It was created in the my_tennis_club root folder, and has the filename db.sqlite3. By default, all Models created in the Django project will be created as tables in this database.

Now when we have described a Model in the models.py file, we must run a command to actually create the table in the database.

/my_tennis_club/ folder and run this command: python manage.py makemigrations members Which will result in this output:

members\migrations\0001_initial.py - Create model Member (myworld) C:\Users\

\myworld\my_tennis_club> Django creates a file describing the changes and stores the file in the /migrations/ folder:

from django.db import migrations, models

class Migration(migrations.Migration):

dependencies = [ ]

operations = [ migrations.CreateModel( name='Member', fields=[

], ), ] Note that Django inserts an id field for your tables, which is an auto increment number (first record gets the value 1, the second record 2 etc.), this is the default behavior of Django, you can override it by describing your own id field. The table is not created yet, you will have to run one more command, then Django will create and execute an SQL statement, based on the content of the new file in the /migrations/ folder.

python manage.py migrate Which will result in this output:

Apply all migrations: admin, auth, contenttypes, members, sessions

Applying members.0001_initial... OK (myworld) C:\Users\

\myworld\my_tennis_club>

Member table in you database!

All you have to do is to run this command, with the migration number: python manage.py sqlmigrate members 0001 Which will result in this output:

-- -- Create model Member --