Create SQLite3 database with peewee

[Jim53_1980]

Hello everybody,

I begin with peewee to create SQLite database. When I use the python code example supplied with the documentation, all works correctly but when I do some minor changes (from my point of view), the database is created but an error occurs and the tables are not cretaed.

Peewee original code example :

from peewee import *

# create a peewee database instance -- our models will use this database to
# persist information
DATABASE = SqliteDatabase("test.db")
    
def create_tables():
    with DATABASE as db:
        db.create_tables([User, Relationship, Message])

# model definitions -- the standard "pattern" is to define a base model class
# that specifies which database to use.  then, any subclasses will automatically
# use the correct storage.
class BaseModel(Model):
    class Meta:
        database = DATABASE

# the user model specifies its fields (or columns) declaratively, like django
class User(BaseModel):
    username = CharField(unique=True)
    password = CharField()
    email = CharField()
    join_date = DateTimeField()

# this model contains two foreign keys to user -- it essentially allows us to
# model a "many-to-many" relationship between users.  by querying and joining
# on different columns we can expose who a user is "related to" and who is
# "related to" a given user
class Relationship(BaseModel):
    from_user = ForeignKeyField(User, backref='relationships')
    to_user = ForeignKeyField(User, backref='related_to')

    class Meta:
        # `indexes` is a tuple of 2-tuples, where the 2-tuples are
        # a tuple of column names to index and a boolean indicating
        # whether the index is unique or not.
        indexes = (
            # Specify a unique multi-column index on from/to-user.
            (('from_user', 'to_user'), True),
        )

# a dead simple one-to-many relationship: one user has 0..n messages, exposed by
# the foreign key. a users messages will be accessible as a special attribute,
# User.messages.
class Message(BaseModel):
    user = ForeignKeyField(User, backref='messages')
    content = TextField()
    pub_date = DateTimeField()
    

if __name__ == "__main__":
    create_tables()

Similar code with minor change :

from peewee import *

# create a peewee database instance -- our models will use this database to
# persist information
DATABASE = None
    
def create_tables():
    with DATABASE as db:
        db.create_tables([User, Relationship, Message])

# model definitions -- the standard "pattern" is to define a base model class
# that specifies which database to use.  then, any subclasses will automatically
# use the correct storage.
class BaseModel(Model):
    class Meta:
        database = DATABASE

# the user model specifies its fields (or columns) declaratively, like django
class User(BaseModel):
    username = CharField(unique=True)
    password = CharField()
    email = CharField()
    join_date = DateTimeField()

# this model contains two foreign keys to user -- it essentially allows us to
# model a "many-to-many" relationship between users.  by querying and joining
# on different columns we can expose who a user is "related to" and who is
# "related to" a given user
class Relationship(BaseModel):
    from_user = ForeignKeyField(User, backref='relationships')
    to_user = ForeignKeyField(User, backref='related_to')

    class Meta:
        # `indexes` is a tuple of 2-tuples, where the 2-tuples are
        # a tuple of column names to index and a boolean indicating
        # whether the index is unique or not.
        indexes = (
            # Specify a unique multi-column index on from/to-user.
            (('from_user', 'to_user'), True),
        )

# a dead simple one-to-many relationship: one user has 0..n messages, exposed by
# the foreign key. a users messages will be accessible as a special attribute,
# User.messages.
class Message(BaseModel):
    user = ForeignKeyField(User, backref='messages')
    content = TextField()
    pub_date = DateTimeField()
    

if __name__ == "__main__":
    DATABASE = SqliteDatabase("test.db")
    create_tables()

Please find below the trace back of the error :

Error:
Traceback (most recent call last):
  File "c:\Users\Dell\Documents\Jean-Marie\supaiment\server_app\dbsupaiement.py", line 53, in <module>
    create_tables()
  File "c:\Users\Dell\Documents\Jean-Marie\supaiment\server_app\dbsupaiement.py", line 9, in create_tables
    db.create_tables([User, Relationship, Message])
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\peewee.py", line 3441, in create_tables
    model.create_table(**options)
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\peewee.py", line 6943, in create_table 
    if safe and not cls._schema.database.safe_create_index \
                    ^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\Dell\AppData\Local\Programs\Python\Python311\Lib\site-packages\peewee.py", line 5832, in database
    raise ImproperlyConfigured('database attribute does not appear to '
peewee.ImproperlyConfigured: database attribute does not appear to be set on the model: <Model: User>