SQLAlchemy-使用数据库列名而不是属性名在模型中设置值 [英] SQLAlchemy - set value in model using database column name, not property name

问题描述

我有一个列为TS_TEST_ID的表.我有一个具有以下属性的SQLAlchemy模型:

I have a table with the column TS_TEST_ID. I have a SQLAlchemy model with the following property:

id = Column(u'TS_TEST_ID', INTEGER(), primary_key=True, nullable=False)

只有已知TS_TEST_ID时，有什么方法可以在我的模型类的实例上设置id吗?也就是说，我只知道数据库中列的名称，并且我想以某种方式将其映射到id并在模型上设置id属性.我希望只执行MyModel(**{'TS_TEST_ID':1})即可，但是出现以下错误:

Is there any way to set id on an instance of my model class when only TS_TEST_ID is known? That is, I only know the name of the column in the database, and I want to somehow map that to id and set the id property on my model. I was hoping just doing MyModel(**{'TS_TEST_ID':1}) would work, but I get the following error:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<string>", line 4, in __init__
  File "C:\Python26\lib\site-packages\sqlalchemy\orm\state.py", line 111,
   in initialize_instance
    return manager.events.original_init(*mixed[1:], **kwargs)
  File "C:\Python26\lib\site-packages\sqlalchemy\ext\declarative.py", line 1377,
   in _declarative_constructor
    (k, cls_.__name__))
TypeError: 'TS_TEST_ID' is an invalid keyword argument for MyModel

我宁愿不必为模型中的每一列都定义TS_TEST_ID = Column(u'TS_TEST_ID', INTEGER(), primary_key=True, nullable=False)，甚至不必为返回id属性的名为TS_TEST_ID的方法定义.

I would rather not have to define TS_TEST_ID = Column(u'TS_TEST_ID', INTEGER(), primary_key=True, nullable=False) for every column in my model, either, or even a method called TS_TEST_ID that returns the id property.

推荐答案

这似乎比需要的要复杂，但可以.我希望有一种更直接的方法...

This seems more complicated than it needs to be, but it works. I'm hoping there's a more direct way of doing this...

@staticmethod
def fromFieldHash(h):
    row = MyModel()
    cols = list(row.__table__._columns)
    for k, v in h.iteritems():
        col = find(lambda c: c.key == k, cols)
        # See http://www.sqlalchemy.org/trac/wiki/06Migration#AnImportantExpressionLanguageGotcha
        if col is not None:
            prop = row.__mapper__._columntoproperty[col].key
            setattr(row, prop, v)
    return row

我正在使用的find方法来自最干净的Python查找-in-list功能.

The find method I'm using is from Cleanest Python find-in-list function.

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