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Python

Posted by Rastko Jovic
Rastko Jovic
14,883 Points

Build A Social Network with FLASK ---> Purpose of constantly calling models.initialize()

Why did we put models.initialize() in to run every time app.py is run? Aren't the models(tables) already in the database?

1 Answer

Ryan S
Ryan S
27,276 Points
Ryan S
Ryan S
27,276 Points

Hi Rastko,

def initialize():
    DATABASE.connect()
    DATABASE.create_tables([User, Post, Relationship], safe=True)
    DATABASE.close()

If you look at the .create_tables() line, you'll see the "safe=True" parameter. This is basically the Peewee version of SQL's "IF NOT EXISTS" command when creating a table. So in this case, models.intialize() serves 2 purposes: the first is to check if the tables already exist, and the second is to create them if they don't. If they do exist then everything's ok, it'll just move on. This is like a safety measure in case something happened to your existing database. Maybe it got deleted or changed in some undesirable way.

I hope this answers your question.