peewee Documentation, Release 2.8.1
• Integers, floats, and Decimal numbers.
• Boolean values
• Dates, times and datetimes
• None (NULL)
• Binary data
Creating tables
In order to start using the models, its necessary to create the tables. This is a one-time operation and can be done
quickly using the interactive interpreter. We can create a small helper function to accomplish this:
def create_tables():
database.connect()
database.create_tables([User, Relationship, Message])
Open a python shell in the directory alongside the example app and execute the following:
>>> from app import
*
>>> create_tables()
Note: If you encounter an ImportError it means that either flask or peewee was not found and may not be installed
correctly. Check the Installing and Testing document for instructions on installing peewee.
Every model has a create_table() classmethod which runs a SQL CREATE TABLE statement in the database.
This method will create the table, including all columns, foreign-key constraints, indexes, and sequences. Usually this
is something you’ll only do once, whenever a new model is added.
Peewee provides a helper method Database.create_tables() which will resolve inter-model dependencies
and call create_table() on each model.
Note: Adding fields after the table has been created will required you to either drop the table and re-create it or
manually add the columns using an ALTER TABLE query.
Alternatively, you can use the schema migrations extension to alter your database schema using Python.
Note: You can also write database.create_tables([User, ...], True) and peewee will first check
to see if the table exists before creating it.
Establishing a database connection
You may have noticed in the above model code that there is a class defined on the base model named Meta that sets
the database attribute. Peewee allows every model to specify which database it uses. There are many Meta options
you can specify which control the behavior of your model.
This is a peewee idiom:
DATABASE = 'tweepee.db'
# Create a database instance that will manage the connection and
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