I am using reflection on an existing database
When I try to use polymorphic on a single table, i get an error;
./test
Traceback (most recent call last):
File "Knowhow.py", line 35, in <module>
from Schema import *
File "/home/treeve/qta/Schema.py", line 72, in <module>
class Invoice(Base):
File "/usr/lib/python2.7/site-packages/sqlalchemy/ext/declarative/api.py",
line 50, in __init__
_as_declarative(cls, classname, cls.__dict__)
File "/usr/lib/python2.7/site-packages/sqlalchemy/ext/declarative/base.py",
line 249, in _as_declarative
"table-mapped class." % cls
sqlalchemy.exc.InvalidRequestError: Class <class 'Schema.Invoice'> does not
have a __table__ or __tablename__ specified and does not inherit from an
existing table-mapped class.
The original schema is:
##############
engine = create_engine(login.connection)
metadata = MetaData(bind=engine)
Base = declarative_base(metadata=metadata)
Base.metadata.bind = engine
#Base.metadata.reflect()
Base.metadata.reflect(views=True)
class X(object):
pass
db=X()
class Doc(Base):
__tablename__ = "doc"
__table_args__ = {'extend_existing': True}
# id = Column(SMALLINT,primary_key=True)
# tdate = Column(Date)
# net = Column(Numeric)
# vat = Column(Numeric)
type = Column(String(1))
__mapper_args__ = {
'polymorphic_identity':'x',
'polymorphic_on':type
}
db.Doc = Doc
class Expense(Base):
# __tablename__ = "expense"
# __table_args__ = {'extend_existing': True}
id = Column(SMALLINT, ForeignKey('doc.id'),primary_key=True)
org = Column(SMALLINT, ForeignKey('org.id'))
__mapper_args__ = {
'polymorphic_identity':'E',
# 'polymorphic_identity':'expense',
}
expenses = relationship("Expitem", backref="exp")
db.Expense = Expense
class Invoice(Base):
# __tablename__ = "invoice"
# __table_args__ = {'extend_existing': True}
id = Column(SMALLINT, ForeignKey('doc.id'),primary_key=True)
org = Column(SMALLINT, ForeignKey('org.id'))
__mapper_args__ = {
'polymorphic_identity':'I',
# 'polymorphic_identity':'invoice',
}
items = relationship("Item", backref="invoice")
db.Invoice = Invoice
try:
Base.metadata.create_all()
except Exception, e:
print 'unable to access database, check the username/password\n',e
sys.exit()
########################
If I activate __tablename__ and __table_args__ for Invoice and Expense,
sqlalchemy generates SQL which references non-existant tables.
If I manually add views for Invoice and Expense everything works.
I am using latest rel_0_8 branch
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