Multiple classes found for path "User" in the registry of this declarative base

[tonyhart7]

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Example Code

sqlalchemy.exc.InvalidRequestError: Multiple classes found for path "User" in the registry of this declarative base. Please use a fully module-qualified path.

Description

I want to make relationship to my table but this error keep happening

Operating System

Windows

Operating System Details

Windows11

FastAPI Version

0.70.1

Python Version

Python 3.10.0

Additional Context

No response

[insomnes]

You know it's rly hard to help you with the error only and no code.

[panla]

There may be more than one user (Base) in the project, and it belonging to Sqlalchemy.

[tonyhart7]

You know it's rly hard to help you with the error only and no code.

the thing is exception from sqlalchemy not from my code

[tonyhart7]

There may be more than one user (Base) in the project, and it belonging to Sqlalchemy.

that the strange part, its only 1 class User in my code

[insomnes]

the thing is exception from sqlalchemy not from my code

Yeah, it is. But without any reproducible code it's very hard to say what causes it.

[tonyhart7]

the thing is exception from sqlalchemy not from my code

Yeah, it is. But without any reproducible code it's very hard to say what causes it.

class Post(Base):
    __tablename__ = "posts"
    __table_args__ = {'extend_existing': True}
    
    id = Column(Integer, primary_key=True, nullable=False)
    title = Column(String, nullable=False)
    content = Column(String, nullable=False)
    published = Column(Boolean, server_default='TRUE', nullable=False)
    created_at = Column(TIMESTAMP(timezone=True),
                        nullable=False, server_default=text('now()'))
    owner_id = Column(Integer, ForeignKey(
        "users.id", ondelete="CASCADE"), nullable=False)

    owner = relationship("User")

class User(Base):
    __tablename__ = "users"
    __table_args__ = {'extend_existing': True}
    
    id = Column(Integer, primary_key=True, nullable=False)
    email = Column(String, nullable=False, unique=True)
    password = Column(String, nullable=False)
    created_at = Column(TIMESTAMP(timezone=True),
                        nullable=False, server_default=text('now()'))

[xdewx]

the thing is exception from sqlalchemy not from my code

Yeah, it is. But without any reproducible code it's very hard to say what causes it.

class Post(Base):
    __tablename__ = "posts"
    __table_args__ = {'extend_existing': True}
    
    id = Column(Integer, primary_key=True, nullable=False)
    title = Column(String, nullable=False)
    content = Column(String, nullable=False)
    published = Column(Boolean, server_default='TRUE', nullable=False)
    created_at = Column(TIMESTAMP(timezone=True),
                        nullable=False, server_default=text('now()'))
    owner_id = Column(Integer, ForeignKey(
        "users.id", ondelete="CASCADE"), nullable=False)

    owner = relationship("User")

class User(Base):
    __tablename__ = "users"
    __table_args__ = {'extend_existing': True}
    
    id = Column(Integer, primary_key=True, nullable=False)
    email = Column(String, nullable=False, unique=True)
    password = Column(String, nullable=False)
    created_at = Column(TIMESTAMP(timezone=True),
                        nullable=False, server_default=text('now()'))

hey, i came across the same question, how did you solve it?

[Chibuoyimm]

in the bracket where you define the class name, embed the path to the class. for example, if your models file is in a folder, you write something like: owner = relationship("folder_name.file_name.class_name"). hope this helps!