Django for Designers/Adding models: Difference between revisions

== Part 3: Models and our database ==

 

Remember to make a new branch for section 3 based off the official branch!

<div class="instructor">The tag slug is stored in another CharField, which we've seen before. But what's this ManyToManyField? Well, it's one type of field for denoting a relationship between two models.

 

 

With a ManyToManyField, on the other hand, the relationship isn't exclusive for either of the models involved. For instance, you could imagine having a Pizza model and a Topping model. Each Pizza can have multiple Toppings, and each Topping can be on multiple Pizzas.

 

More information on making queries with Django's ORM can be found in the Django docs at https://docs.djangoproject.com/en/dev/topics/db/queries/#retrieving-objects.

 

== Part 3.5: Changing our mind and adding users ==

 

<div class="instructor">D'oh! You know what every social bookmarking app has, that ours doesn't have? Users!

 

<source lang="python">

>>> import random

>>> # Create the Tag objects

>>> for tag_name in tag_names:

... tag.save()

...

>>> kids_urls = ['http://pbskids.org/', 'http://www.clubpenguin.com/', 'http://www.aplusmath.com/hh/index.html', 'http://kids.nationalgeographic.com/kids/activities/recipes/lucky-smoothie/', 'http://www.handwritingforkids.com/', 'http://pinterest.com/catfrilda/origami-for-kids/', 'http://richkidsofinstagram.tumblr.com/', 'http://www.dorkly.com/picture/50768/', 'http://www.whyzz.com/what-is-paint-made-of', 'http://yahooligans.com/']

>>> for kids_url in kids_urls:

... b.save()

... how_many_tags = random.randrange(len(tag_names))

... for tag_name in random.sample(tag_names, how_many_tags):

...

>>> b.title = "Yahoooo!!!!!ligans"

>>> b.save()

{% extends 'index.html' %}

 

</source>

 

Save and commit your error-catching work.

 

 

So far, we've all only been able to access our own Django-powered sites. In this section, you will see how to access my (the instructor's) super cool bookmarks site! (We'll talk later about how you can share your code the same way. It might require firewall configuration changes on your computer, so we save that complexity for later.)

 

When you visit the instructor's app, you are interacting with the database stored on her laptop. So all the changes made by other people in the room are reflected in what you see! So try not to be too silly.

 

<!-- Instructor git note: git push origin HEAD:pre-part-4 00-->