В настоящее время я пытаюсь сопоставить существующее представление в моей базе данных postgreSQL с объектом ORM SqlAlchemy в python. Мое представление имеет следующее имя path_number_view и объединяет несколько таблиц. Это хорошо работает. Но я не могу отобразить представление на объект ORM, при запуске приложения я получаю сообщение об ошибке (ниже кода).
Я следовал этим инструкциям,
, но я не могу заставить это работать.
Вот мой код:
engine = create_engine("postgresql://****:*****@localhost/pi", pool_size=15, max_overflow=5, pool_recycle=1200)
Base = declarative_base(engine)
metadata = MetaData(engine)
path_number_view = Table('path_number_view', metadata,
Column('id', Integer, primary_key=True),
Column('path', String),
Column('threeDaysL', Integer),
Column('threeDaysC', Integer),
Column('tenDaysL', Integer),
Column('tenDaysC', Integer),
Column('number', Integer),
autoload=True
)
class PathNumberView(object):
__tablename__ = 'path_number_view'
def __init__(self, id, path, threeDaysL, threeDaysC, tenDaysL, tenDaysC, number):
self.id = id
self.path = path
self.threeDaysL = threeDaysL
self.threeDaysC = threeDaysC
self.tenDaysL = tenDaysL
self.tenDaysC = tenDaysC
self.number = number
mapper(PathNumberView, path_number_view )
Base.metadata.create_all(engine)
Ошибка, которую я получаю, не помогает :
Traceback (most recent call last):
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\base.py", line 2265, in _wrap_pool_connect
return fn()
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 363, in connect
return _ConnectionFairy._checkout(self)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 760, in _checkout
fairy = _ConnectionRecord.checkout(pool)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 492, in checkout
rec = pool._do_get()
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\impl.py", line 139, in _do_get
self._dec_overflow()
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\util\langhelpers.py", line 68, in __exit__
compat.reraise(exc_type, exc_value, exc_tb)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\util\compat.py", line 153, in reraise
raise value
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\impl.py", line 136, in _do_get
return self._create_connection()
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 308, in _create_connection
return _ConnectionRecord(self)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 437, in __init__
self.__connect(first_connect_check=True)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 639, in __connect
connection = pool._invoke_creator(self)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\strategies.py", line 114, in connect
return dialect.connect(*cargs, **cparams)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\default.py", line 453, in connect
return self.dbapi.connect(*cargs, **cparams)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\psycopg2\__init__.py", line 126, in connect
conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
psycopg2.OperationalError
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "C:\Program Files\JetBrains\PyCharm 2018.3.5\helpers\pycharm\_jb_unittest_runner.py", line 35, in <module>
main(argv=args, module=None, testRunner=unittestpy.TeamcityTestRunner, buffer=not JB_DISABLE_BUFFERING)
File "C:\Users\username\.conda\envs\tfGPU2\lib\unittest\main.py", line 94, in __init__
self.parseArgs(argv)
File "C:\Users\username\.conda\envs\tfGPU2\lib\unittest\main.py", line 141, in parseArgs
self.createTests()
File "C:\Users\username\.conda\envs\tfGPU2\lib\unittest\main.py", line 148, in createTests
self.module)
File "C:\Users\username\.conda\envs\tfGPU2\lib\unittest\loader.py", line 219, in loadTestsFromNames
suites = [self.loadTestsFromName(name, module) for name in names]
File "C:\Users\username\.conda\envs\tfGPU2\lib\unittest\loader.py", line 219, in <listcomp>
suites = [self.loadTestsFromName(name, module) for name in names]
File "C:\Users\username\.conda\envs\tfGPU2\lib\unittest\loader.py", line 153, in loadTestsFromName
module = __import__(module_name)
File "E:\Projekte\project\preprocessing\tests.py", line 6, in <module>
from preprocessing.data import TrainingDataProvider
File "E:\Projekte\project\preprocessing\data\__init__.py", line 7, in <module>
from entity import PathNumberView
File "E:\Projekte\project\entity\__init__.py", line 105, in <module>
Base.metadata.create_all(engine)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\sql\schema.py", line 4294, in create_all
ddl.SchemaGenerator, self, checkfirst=checkfirst, tables=tables
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\base.py", line 2035, in _run_visitor
with self._optional_conn_ctx_manager(connection) as conn:
File "C:\Users\username\.conda\envs\tfGPU2\lib\contextlib.py", line 81, in __enter__
return next(self.gen)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\base.py", line 2027, in _optional_conn_ctx_manager
with self._contextual_connect() as conn:
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\base.py", line 2229, in _contextual_connect
self._wrap_pool_connect(self.pool.connect, None),
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\base.py", line 2269, in _wrap_pool_connect
e, dialect, self
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\base.py", line 1536, in _handle_dbapi_exception_noconnection
util.raise_from_cause(sqlalchemy_exception, exc_info)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\util\compat.py", line 398, in raise_from_cause
reraise(type(exception), exception, tb=exc_tb, cause=cause)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\util\compat.py", line 152, in reraise
raise value.with_traceback(tb)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\base.py", line 2265, in _wrap_pool_connect
return fn()
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 363, in connect
return _ConnectionFairy._checkout(self)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 760, in _checkout
fairy = _ConnectionRecord.checkout(pool)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 492, in checkout
rec = pool._do_get()
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\impl.py", line 139, in _do_get
self._dec_overflow()
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\util\langhelpers.py", line 68, in __exit__
compat.reraise(exc_type, exc_value, exc_tb)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\util\compat.py", line 153, in reraise
raise value
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\impl.py", line 136, in _do_get
return self._create_connection()
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 308, in _create_connection
return _ConnectionRecord(self)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 437, in __init__
self.__connect(first_connect_check=True)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\pool\base.py", line 639, in __connect
connection = pool._invoke_creator(self)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\strategies.py", line 114, in connect
return dialect.connect(*cargs, **cparams)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\sqlalchemy\engine\default.py", line 453, in connect
return self.dbapi.connect(*cargs, **cparams)
File "C:\Users\username\.conda\envs\tfGPU2\lib\site-packages\psycopg2\__init__.py", line 126, in connect
conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
sqlalchemy.exc.OperationalError: (psycopg2.OperationalError)
(Background on this error at: http://sqlalche.me/e/e3q8)
Соединение само по себе работает, у меня есть 3 другие таблицы (созданные с помощью SQLAclhemy), которые работают нормально. Я могу запросить, обновить, удалить без проблем.