Question: In one of our project, we used SQL Alchemy declarative Base for all of our models for years (and there is many). We want to try the new SQLModel library for our latest model declaration. For that, we tried to declare it separately from the Base object, and call the create_all methods for both. i.e : Base.metadata.create_all() and SQLModel.metadata.create_all(). But the model declared with SQLModel does not recognize the table declared with the Base. And at this moment, we cannot change all previous models declaration from Base to SQLModel. Here is a reproducible code : from sqlalchemy.ext.declarative import declarative_base from sqlalchemy import Column from sqlalchemy import Integer from typing import Optional from sqlmodel import Field, SQLModel from sqlalchemy import String # Declarative base object Base = declarative_base() class DummySATable(Base): __tablename__ = 'dummy_table' id = Column(Integer, primary_key=True, autoincrement=True) name = Column(String(32)) class DummyModelTable(SQLModel, table=True): id: Optional[int] = Field(default=None, primary_key=True) dummy_table_id : int = Field(default=None, foreign_key='dummy_table.id') name: str Base.metadata.create_all(engine) SQLModel.metadata.create_all(engine)  Here is the traceback : NoReferencedTableError Traceback (most recent call last) /tmp/ipykernel_307893/3665898561.py in <module> 24 25 Base.metadata.create_all(engine) ---> 26 SQLModel.metadata.create_all(engine) 27 ~/project/venv/lib/python3.9/site-packages/sqlalchemy/sql/schema.py in create_all(self, bind, tables, checkfirst) 4783 if bind is None: 4784 bind = _bind_or_error(self) -> 4785 bind._run_ddl_visitor( 4786 ddl.SchemaGenerator, self, checkfirst=checkfirst, tables=tables 4787 ) ~/project/venv/lib/python3.9/site-packages/sqlalchemy/engine/base.py in _run_ddl_visitor(self, visitorcallable, element, **kwargs) 3108 def _run_ddl_visitor(self, visitorcallable, element, **kwargs): 3109 with self.begin() as conn: -> 3110 conn._run_ddl_visitor(visitorcallable, element, **kwargs) 3111 3112 @util.deprecated_20( ~/project/venv/lib/python3.9/site-packages/sqlalchemy/engine/base.py in _run_ddl_visitor(self, visitorcallable, element, **kwargs) 2111 2112 """ -> 2113 visitorcallable(self.dialect, self, **kwargs).traverse_single(element) 2114 2115 @util.deprecated( ~/project/venv/lib/python3.9/site-packages/sqlalchemy/sql/visitors.py in traverse_single(self, obj, **kw) 522 meth = getattr(v, "visit_%s" % obj.__visit_name__, None) 523 if meth: --> 524 return meth(obj, **kw) 525 526 def iterate(self, obj): ~/project/venv/lib/python3.9/site-packages/sqlalchemy/sql/ddl.py in visit_metadata(self, metadata) 820 tables = list(metadata.tables.values()) 821 --> 822 collection = sort_tables_and_constraints( 823 [t for t in tables if self._can_create_table(t)] 824 ) ~/project/venv/lib/python3.9/site-packages/sqlalchemy/sql/ddl.py in sort_tables_and_constraints(tables, filter_fn, extra_dependencies, _warn_for_cycles) 1284 continue 1285 -> 1286 dependent_on = fkc.referred_table 1287 if dependent_on is not table: 1288 mutable_dependencies.add((dependent_on, table)) ~/project/venv/lib/python3.9/site-packages/sqlalchemy/sql/schema.py in referred_table(self) 3703 3704 """ -> 3705 return self.elements[0].column.table 3706 3707 def _validate_dest_table(self, table): ~/project/venv/lib/python3.9/site-packages/sqlalchemy/util/langhelpers.py in __get__(self, obj, cls) 1111 if obj is None: 1112 return self -> 1113 obj.__dict__[self.__name__] = result = self.fget(obj) 1114 return result 1115 ~/project/venv/lib/python3.9/site-packages/sqlalchemy/sql/schema.py in column(self) 2408 2409 if tablekey not in parenttable.metadata: -> 2410 raise exc.NoReferencedTableError( 2411 "Foreign key associated with column '%s' could not find " 2412 "table '%s' with which to generate a " NoReferencedTableError: Foreign key associated with column 'dummymodeltable.dummy_table_id' could not find table 'dummy_table' with which to generate a foreign key to target column 'id'  What did I missed? Is it even possible (is there any workaround ?)

Answer: I've finally found a simple way to do that, according to this thread. Since SQLModel inherits the Metadata object from SQLAlchemy, We can simply bind the metadata object of SQLModel to the metadata object from SQLAlchemy : # Declarative base object Base = declarative_base() SQLModel.metadata = Base.metadata # Table declaration.... SQLModel.metadata.create_all(engine)