How to use two different metadata properly to connect to two databases?

First Check

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• I already checked if it is not related to SQLModel but to SQLAlchemy.

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Example Code

from typing import Optional

from sqlmodel import Field, SQLModel
import sqlalchemy

metadata1 = sqlalchemy.MetaData()
metadata2 = sqlalchemy.MetaData()

# all_metadata = sqlmodel.SQLModel.metadata

class Hero(SQLModel, table=True):
    id: Optional[int] = Field(default=None, primary_key=True)
    name: str
    secret_name: str
    age: Optional[int] = None
    __table_args__ = (
        metadata1,  # This setting has no effect !! :(
    )

class Boss(SQLModel, table=True):
    id: Optional[int] = Field(default=None, primary_key=True)
    name: str
    age: Optional[int] = None
    __table_args__ = (
        metadata2,  # This setting has no effect !! :(
    )

engine1 = sqlalchemy.create_engine("database 1")
engine2 = sqlalchemy.create_engine("database 2")

metadata1.create_all(engine1)
metadata2.create_all(engine2)

## in alembic's env.py
# target_metadata = {
#    'engine1': mymodel.metadata1,
#    'engine2': mymodel.metadata2
#}

Description

• I want to use two databases that have different table groups.
• SQLModel provides only one metadata (sqlmodel.SQLModel.metadata)

Operating System

Linux

Operating System Details

No response

SQLModel Version

0.0.6

Python Version

3.10.0

Additional Context

No response

[vn7n24fzkq]

I finally found a simple way to create tables in different databases.

import uuid as uuid_pkg
from typing import Optional

from sqlalchemy.orm import registry
from sqlmodel import Field, SQLModel, create_engine


class DB1Base(SQLModel, registry=registry()):
    pass
    
class DB2Base(SQLModel, registry=registry()):
    pass

class DB1Table(DB1Base, table=True):
    uuid: Optional[uuid_pkg.UUID] = Field(default_factory=uuid_pkg.uuid4, primary_key=True)
    name: str = Field(nullable=False, index=True, unique=True)

class DB2Table(DB2Base, table=True):
    uuid: Optional[uuid_pkg.UUID] = Field(default_factory=uuid_pkg.uuid4, primary_key=True)
    name: str = Field(nullable=False, index=True, unique=True)

db1_engine = create_engine("postgresql://postgres@localhost:5432/db1")
db2_engine = create_engine("postgresql://postgres@localhost:5432/db2")

DB1Base.metadata.create_all(db1_engine)
DB2Base.metadata.create_all(db2_engine)

[byrman]

This seems to work, although I did not test is thoroughly:

class SQLModel1(SQLModel):
    metadata = MetaData()


class SQLModel2(SQLModel):
    metadata = MetaData()


...


SQLModel1.metadata.create_all(engine1)
SQLModel2.metadata.create_all(engine2)