SQLalchemy not find table for creating foreign key

Question

I have a problem with SQL Alchemy, while trying to create a database, i get:

"sqlalchemy.exc.NoReferencedTableError: Foreign key associated with column 'estate_agent.person_id' could not find table 'person' with which to generate a foreign key to target column 'id'" 

Meta datas:

db = create_engine('postgresql+psycopg2:...//') meta = MetaData() meta.bind = db 

Person table:

tbl_person = Table(    'person', meta,    Column('id', Integer, Sequence('seq_person_id'), primary_key=True),    Column('name', String(100), unique=True, nullable = False),    Column('password', String(40), nullable = False),    Column('person_type_id', Integer, ForeignKey("person_type.id"), nullable = False),    Column('register_date', DateTime, default = datetime.now),    Column('pendencies', String(200)),    Column('active', Boolean, default = True),    schema = 'public') 

Bug Table:

tbl_estate_agent = Table(    'estate_agent', meta,    Column('person_id', Integer, ForeignKey("person.id"), primary_key = True),    Column('prize_range_id', Integer, ForeignKey("prize_range.id"), nullable = False),    schema = 'public') 

Normal table (creating normally the fk)

tbl_person_agent = Table(    'person_agent', meta,    Column('person_id', Integer, ForeignKey("person.id"), primary_key = True),    Column('prize_range_id', Integer, ForeignKey("prize_range.id"), nullable = False),    schema = 'public') 

Creation Call:

meta.create_all(checkfirst=True) 

Complete error log:

Traceback (most recent call last):    File "database_client.py", line 159, in <module>     meta.create_all(checkfirst=True)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/schema.py", line 3404, in create_all     tables=tables)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/engine/base.py", line 1616, in _run_visitor     conn._run_visitor(visitorcallable, element, **kwargs)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/engine/base.py", line 1245, in _run_visitor     **kwargs).traverse_single(element)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/visitors.py", line 120, in traverse_single     return meth(obj, **kw)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/ddl.py", line 699, in visit_metadata     collection = [t for t in sort_tables(tables)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/ddl.py", line 862, in sort_tables     {'foreign_key': visit_foreign_key})    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/visitors.py", line 256, in traverse     return traverse_using(iterate(obj, opts), obj, visitors)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/visitors.py", line 247, in traverse_using     meth(target)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/ddl.py", line 853, in visit_foreign_key     parent_table = fkey.column.table   File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/util/langhelpers.py", line 725, in __get__     obj.__dict__[self.__name__] = result = self.fget(obj)    File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/sql/schema.py", line 1720, in column tablekey) sqlalchemy.exc.NoReferencedTableError: Foreign key associated with column 'estate_agent.person_id' could not find table 'person' with which to generate a foreign key to target column 'id' 

Answer 1

The solution is to replace the strings with actual columns:

Column('person_id', Integer, ForeignKey(tbl_person.c.id), primary_key=True) 

Answer 2

By adding the following line to my parent table solved my problem. In case of Declarative:

children = relationship("Child") 

Otherwise: SQLAlchemy - Classic Mapper

Also try to have a look in here (SO) too, might help.