[Sqlalchemy-tickets] Issue #3123: mysql reflection on python-2.6 causes error (zzzeek/sqlalchemy)

[barnabas79 <iss...@bi...>]

New issue 3123: mysql reflection on python-2.6 causes error
https://bitbucket.org/zzzeek/sqlalchemy/issue/3123/mysql-reflection-on-python-26-causes-error

barnabas79:

The essential problem is that mysql seems to return some table names as unicode, and in python 2.6, you can't use unicode as keys in a dict that you're unpacking for function kwargs - ie, in python 2.6, this:


```
#!python

def foo(**kwargs):
    print kwargs
foo(**{u'thing':1})
```

will raise an error:


```
#!python

TypeError: foo() keywords must be strings
```

To replicate:

* Set up a mysql server
    * On fedora 19, I just did:
        * yum install mysql-server
        * service mysqld start
* Using **python-2.6**, Run the following code (assuming you're connecting to the server running on the same machine, and that there's a database called "test", which should exist by default):


```
#!python

from sqlalchemy import create_engine
from sqlalchemy import Table, Column, Integer, String, MetaData, ForeignKey

# connect to the "test" database, which should be set up by default

DEFAULT_DB_HOST = 'sv-db05'
engine = create_engine("mysql+mysqldb://127.0.0.1/test", echo=True)

# Set up a basic table

metadata = MetaData()
users = Table(
    'users', metadata,
    Column('id', Integer, primary_key=True),
    Column('name', String(255)),
)
metadata.create_all(engine)

# now reflect..

metadata2 = MetaData()
metadata2.reflect(engine, only=['users'])
```

This should raise this error:


```
#!python

Traceback (most recent call last):
  File "<stdin>", line 22, in <module>
    metadata2.reflect(engine, only=['users'])
  File "./sqlalchemy/lib/sqlalchemy/sql/schema.py", line 3288, in reflect
    Table(name, self, **reflect_opts)
  File "./sqlalchemy/lib/sqlalchemy/sql/schema.py", line 353, in __new__
    table._init(name, metadata, *args, **kw)
  File "./sqlalchemy/lib/sqlalchemy/sql/schema.py", line 426, in _init
    self._autoload(metadata, autoload_with, include_columns)
  File "./sqlalchemy/lib/sqlalchemy/sql/schema.py", line 438, in _autoload
    self, include_columns, exclude_columns
  File "./sqlalchemy/lib/sqlalchemy/engine/base.py", line 1239, in run_callable
    return callable_(self, *args, **kwargs)
  File "./sqlalchemy/lib/sqlalchemy/engine/default.py", line 356, in reflecttable
    return insp.reflecttable(table, include_columns, exclude_columns)
  File "./sqlalchemy/lib/sqlalchemy/engine/reflection.py", line 474, in reflecttable
    for col_d in self.get_columns(table_name, schema, **table.dialect_kwargs):
TypeError: get_columns() keywords must be strings
```