django part-1
- 7. The model provides data from the database. In Django, the data is delivered as an Object Relational Mapping (ORM), which is a technique designed to make it easier to work with databases. The most common way to extract data from a database is SQL. One problem with SQL is that you have to have a pretty good understanding of the database structure to be able to work with it. Django, with ORM, makes it easier to communicate with the database, without having to write complex SQL statements. The models are usually located in a file called models.py.
- 9. A template is a file where you describe how the result should be represented. Templates are often .html files, with HTML code describing the layout of a web page, but it can also be in other file formats to present other results, but we will concentrate on .html files. Django uses standard HTML to describe the layout, but uses Django tags to add logic: <h1>My Homepage</h1> <p>My name is {{ firstname }}.</p> The templates of an application is located in a folder named templates.
- 10. Django also provides a way to navigate around the different pages in a website. When a user requests a URL, Django decides which view it will send it to. This is done in a file called urls.py.
- 11. 1 - Django receives the URL, checks the urls.py file, and calls the view that matches the URL. 2 - The view, located in views.py, checks for relevant models. 3 - The models are imported from the models.py file. 4 - The view then sends the data to a specified template in the template folder. 5 - The template contains HTML and Django tags, and with the data it returns finished HTML content back to the browser.
- 17. Note: You must activate the virtual environment every time you open the command prompt to work on your project.
- 18. Note: Now you have installed Django in your new project, running in a virtual environment!
- 21. Navigate to where in the file system you want to store the code (in the virtual environment), and run this command in the command prompt: django-admin startproject myworld
- 22. Django creates a myworld folder on my computer, with this content: myworld manage.py myworld/ __init__.py asgi.py settings.py urls.py wsgi.py
- 23. Now that you have a Django project, you can run it, and see what it looks like in a browser. Navigate to the /myworld folder and execute this command in the command prompt: py manage.py runserver
- 30. Django views are Python functions that takes http requests and returns http response, like HTML documents. A web page that uses Django is full of views with different tasks and missions. Views are usually put in a file called views.py located on your app's folder.
- 42. When we created the Django project, we got an empty SQLite database. It was created in the myworld root folder. We will use this database in this session.
- 55. To add some HTML around the values, we will create a template for the application. All templates must be located in the templates folder off your app, if you have not already created a templates folder, do it now.