如何在 Sybase 中使用 SQLAlchemy 反射？ [答案：原来不支持！]

Question

我正在尝试更多地了解 Python 中的 .egg 概念和覆盖方法。这是我收到的错误消息：

Traceback (most recent call last):
  File "C:/local/work/scripts/plmr/plmr_db.py", line 42, in <module>
    insp.reflecttable(reo_daily_table, column_list)
  File "build\bdist.win32\egg\sqlalchemy\engine\reflection.py", line 370, in reflecttable
  File "build\bdist.win32\egg\sqlalchemy\engine\reflection.py", line 223, in get_columns
  File "build\bdist.win32\egg\sqlalchemy\engine\base.py", line 260, in get_columns
NotImplementedError

下面是 base.py 中的具体函数：

def get_columns(self, connection, table_name, schema=None, **kw):
    """Return information about columns in `table_name`.

    Given a :class:`.Connection`, a string
    `table_name`, and an optional string `schema`, return column
    information as a list of dictionaries with these keys:

    name
      the column's name

    type
      [sqlalchemy.types#TypeEngine]

    nullable
      boolean

    default
      the column's default value

    autoincrement
      boolean

    sequence
      a dictionary of the form
          {'name' : str, 'start' :int, 'increment': int}

    Additional column attributes may be present.
    """

    raise NotImplementedError()

所以我的问题是 - 我是否通过在我的主模块中编写一个新方法来覆盖这个函数？还是我在导入的过程中遗漏了一步？还是我完全偏离了轨道？

感谢您的任何帮助:)

编辑：添加我的代码

import sys
from sqlalchemy import create_engine, select, Table, MetaData
from sqlalchemy.engine import reflection

dbPath = 'connection_string'
engine = create_engine(dbPath, echo=True)

connection = engine.connect()

#reflect tables into memory
meta = MetaData()
reo_daily_table = Table('reo_daily',meta)
insp = reflection.Inspector.from_engine(engine)
column_list=[...]
insp.reflecttable(reo_daily_table, column_list)

connection.close()

Answer 1

你完全误解了。您不需要对任何东西进行子类化，而且这个问题与鸡蛋和 .ini 文件完全无关。

您不应该以这种方式实例化 Inspector。如果你读 SQLAlchemy docs 仔细，你会注意到你不应该直接使用反射构造函数；相反，你应该写

insp = reflection.Inspector.from_engine(engine)

Answer 2

编辑：

The Sybase dialect currently lacks the ability to reflect tables.