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SQLalchemy creates Database, but not tables

I'm trying to connect my FastAPI project to 2 databases, one is gonna be local and the other one is located in an IP address. I think I managed to connect to both. However, when I try to create the local db, I get the file of the file, but is not pulling the models that I created for that db.
my code for database.py is the following:
SQLALCHEMY_DATABASE_URL = "credentials and address"
AUTH_DATABASE_URL = "sqlite:///./users.db"
engine = create_engine(SQLALCHEMY_DATABASE_URL)
engine2 = create_engine(AUTH_DATABASE_URL, connect_args={
"check_same_thread": False})
Base = declarative_base()
BaseB = declarative_base()
SessionLocal = sessionmaker(autocommit=False, autoflush=False)
SessionLocal.configure(binds={Base: engine, BaseB: engine2})
The models I created for that base are the following:
class User(BaseB):
__tablename__ = "users"
Id = Column(Integer, primary_key=True, index=True)
email = Column(String, unique=True, index=True)
hashed_password = Column(String)
##Constraints##
leads = relationship("Lead", back_populates="owner")
def verify_password(self, password: str):
return hash.bcrypt.verify(password, self.hashed_password)
class Lead(BaseB):
__tablename__ = "leads"
Id = Column(Integer, primary_key=True, index=True)
owner_id = Column(Integer, ForeignKey("users.Id"))
first_name = Column(String, index=True)
last_name = Column(String, index=True)
email = Column(String, index=True)
company = Column(String, index=True, default="")
notes = Column(String, default="")
date_created = Column(String, default=datetime.utcnow)
date_last_update = Column(String, default=datetime.utcnow)
##Constraints##
owner = relationship("User", back_populates="leads")
Also, I created a services.py file, which I use to run the code to create the database. It's creating the users.db file, but when I try to open it, I don't get the tables I created:
from database import BaseB, engine2, SessionLocal
def create_database():
return BaseB.metadata.create_all(bind=engine2)
def get_db():
db = SessionLocal()
try:
yield db
finally:
db.close()
This is causing me problems, because I need to post data to the table users. However, when I try to do it, I get an error saying there is no such table created. I've tried even to run the code to generate the db automatically (without running services.py on python) but still I get the same error.
I would appreciate if someone can take a look at my code and check what I may be missing.
Thanks!!

Thank you!
I think I have figured out what was wrong. I post this solution in case anyone else might get trapped as I was. My error was that I wasn't importing the models, neither declaring it in the services.py route. I changed my code and now I can see the two tables when I create the database from python
from database import engine2, SessionLocal
import models
def create_database():
return models.BaseB.metadata.create_all(bind=engine2)
Hope it helps anyone having the same problem :)

Flask-Sqlalchemy create views with postgres

I am using a Flask-Sqlalchemy postgres database model with the following style:
class User(db.Model) // Holds the users
id = db.Column(db.Integer, primary_key=True)
...
class Track(db.Model) // Holds racing tracks
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(255), nullable=False)
class Record(db.Model) // Hold users records on tracks
id = db.Column(db.Integer, primary_key=True)
user_id = db.Column(db.Integer, db.ForeignKey("user.id"), primary_key=True)
track_id = db.Column(db.Integer, db.ForeignKey("map.id"), primary_key=True)
time = db.Column(db.BigInteger, nullable=False)
My goal now would be to create a view which holds all Tracks completed by Users. In plain PostgresSQL it would look like this:
CREATE VIEW OR REPLACE user_tracks_finished AS
SELECT DISTINCT user_id, track_id
FROM record;
The User model would look something like this:
class User(db.Model) // Holds the users
id = db.Column(db.Integer, primary_key=True)
finished_tracks = db.relationship(...)
I can not any way to create views with the flask-sqlalchemy module. There is a sqlalchemy-views module, which I can not get to run in my flask app. Anybody got a good idea on how to model something like this? Any help ist appreciated!

I managed to get it done with SQLAlchemy-Utils: https://pypi.org/project/SQLAlchemy-Utils/
from sqlalchemy_utils import create_view
class UserFinishedMaps(db.Model):
__table__ = create_view(
name="user_finished_maps",
selectable=select([Record.user_id, Record.map_id]).group_by(
Record.user_id, Record.map_id
),
metadata=db.metadata,
)

Flask-SQLAlchemy 'NoForeignKeysError'

I am working on a Flask app, using Flask-SQLAlchemy extension for database interactions. Since I have multiple apps writing on the same DB, I was getting concurrency issues with SQLite and I wanted to switch to PostgreSQL instead. I am able to create the tables on new database without a problem and pgAdmin displays the tables and columns.
# working
def createTables():
with app.app_context():
from models import User, Invoice
db.create_all()
But when it comes to adding a user, I am now getting an error: sqlalchemy.exc.NoForeignKeysError Although, I think, I declared one-to-many relationship in my models, based on the documentation, I get an error states that "there are no foreign keys linking these tables."
# not working
def create_test_user():
with app.app_context():
user = User(
username="Bob",
email="bob#email.com",
password="test"
)
db.session.add(user)
db.session.commit()
The full error message:
""" NoForeignKeysError: Could not determine join condition between parent/child tables on relationship User.invoices
- there are no foreign keys linking these tables.
Ensure that referencing columns are associated with a ForeignKey or ForeignKeyConstraint, or specify a 'primaryjoin' expression. """
I can't figure out what causes the error. What is missing with my models?
# models.py
class User(db.Model):
__tablename__ = "user"
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(20), unique=True, nullable=False)
email = db.Column(db.String(120), unique=True, nullable=False)
password = db.Column(db.String(60), nullable=False)
invoices = db.relationship('Invoice', backref='user', lazy=True)
class Invoice(db.Model):
__tablename__ = "invoice"
id = db.Column(db.Integer, primary_key=True)
user_id = db.Column(db.Integer, db.ForeignKey('user.id'), nullable=False)
amount = db.Column(db.Integer, nullable=False)
Solved

Your code works for me. Maybe you need to re-create your tables or something similar. To be sure that we have the identical code: I have tested the following code:
class User(db.Model):
__tablename__ = "user"
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(20), unique=True, nullable=False)
email = db.Column(db.String(120), unique=True, nullable=False)
password = db.Column(db.String(60), nullable=False)
invoices = db.relationship('Invoice', backref='user', lazy=True)
class Invoice(db.Model):
__tablename__ = "invoice"
id = db.Column(db.Integer, primary_key=True)
user_id = db.Column(db.Integer, db.ForeignKey('user.id'), nullable=False)
amount = db.Column(db.Integer, nullable=False)
In the route:
user = User(
username="Bob",
email="bob#email.com",
password="test"
)
db.session.add(user)
db.session.commit()
print(user)

I finally solved the problem and it was not where I was looking for. I was getting NoForeignKeysError due to importing a wrong model file during initializing the app. One of my imported modules was calling a wrong/old version of the model. It was causing the table relationship in the actual model to break I guess.
When I went through step by step create_test_user() I noticed that the error occurs actually during the class creation, before even it hits to db.session.add and I replicated the error even without a DB. I went through all my modules that are calling the models and caught wrong model import.

Flask-SQLAlchemy creating schema before creating tables

I am trying to configure a MySQL schema using Flask-SQLAlchemy. I have a schema called testdb and some tables. I will list one table, User.
This code, so far, creates all of the tables needed but only when testdb already exists. Is there a way to check and create testdb before I connect?
app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:password#localhost/testdb'
db = SQLAlchemy(app)
class User(db.Model):
userid = db.Column(db.Integer, primary_key=True, autoincrement=True)
username = db.Column(db.String(16), unique=True, nullable=False)
password = db.Column(db.String(16), unique=False, nullable=False)
email = db.Column(db.String(80), unique=True, nullable=False)
createdDate = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
lastUpdated = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
db.create_all()
Desired command:
CREATE SCHEMA IF NOT EXISTS `testdb` ;

I solved this thanks to #hygorxaraujo
See the code below:
import sqlachemy
engine = sqlalchemy.create_engine('mysql://root:password#localhost') # connect to server
engine.execute("CREATE SCHEMA IF NOT EXISTS `testdb`;") #create db
engine.execute("USE testdb;") # select new db
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://root:mypassword#localhost/testdb'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False #Turn off annoying message
db = SQLAlchemy(app)

flask database reset migrate

i have created a database for the Flask application,
class Post(db.Model, SearchableMixin):
__searchable__ = ['body']
id = db.Column(db.Integer, primary_key=True)
body = db.Column(db.String(140))
timestamp = db.Column(db.DateTime, index=True, default=datetime.utcnow)
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
language = db.Column(db.String(5))
# for the comment foreign key
comment = db.relationship('Comment', foreign_keys = 'Comment.post_id',
backref = 'post', lazy = 'dynamic')
photo = db.relationship('Photo', foreign_keys = 'Photo.post_idn',
backref = 'post', lazy = 'dynamic')
def __repr__(self):
return "<Post {}>".format(self.body)
class Photo(db.Model):
id = db.Column(db.Integer, primary_key = True)
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
photo_url = db.Column(db.String(200))
upload_time = db.Column(db.DateTime, index=True, default=datetime.utcnow)
new_field = db.Column(db.String(100))
post_id = db.Column(db.Integer, db.ForeignKey('post.id'))
def __repr__(self):
return '<Photo {}>'.format(self.photo_url)
when i run flask db migrate and upgrade, it states that
[2018-11-25 21:07:03,439] INFO in init: Microblog startup INFO
[alembic.runtime.migration] Context impl SQLiteImpl. INFO
[alembic.runtime.migration] Will assume non-transactional DDL.
However, when I try to run Photo.query.all() in flask shell, it gives me the below errors ' No such column: post_id'
I believe this is a databse migration issue. Any one has any idea what i should do?
And i am willing to delete the whole database and re-migrate everything again. Can someone advice me how to do so. Thanks.

You have created post_id as foreign key. So you must create a Post model for post db table with a column named id.