sqlalchemy and Unicode strings: errormessage

[Benjamin Kaplan]

On Tue, May 31, 2011 at 8:45 AM, Wolfgang Meiners
<WolfgangMeiners01 at web.de> wrote:
> Am 31.05.11 13:32, schrieb Daniel Kluev:
>> On Tue, May 31, 2011 at 8:40 AM, Wolfgang Meiners
>> <WolfgangMeiners01 at web.de> wrote:
>>> metadata = MetaData('sqlite://')
>>> a_table = Table('tf_lehrer', metadata,
>>>    Column('id', Integer, primary_key=True),
>>>    Column('Kuerzel', Text),
>>>    Column('Name', Text))
>>
>> Use UnicodeText instead of Text.
>>
>>> A_record = A_class('BUM', 'Bäumer')
>>
>> If this is python2.x, use u'Bäumer' instead.
>>
>>
>
> Thank you Daniel.
> So i came a little bit closer to the solution. Actually i dont write the
> strings in a python program but i read them from a file, which is
> utf8-encoded.
>
> So i changed the lines
>
>    for line in open(file,'r'):
>        line = line.strip()
>
> first to
>
>    for line in open(file,'r'):
>        line = unicode(line.strip())
>
> and finally to
>
>    for line in open(file,'r'):
>        line = unicode(line.strip(),'utf8')
>
> and now i get really utf8-strings. It does work but i dont know why it
> works. For me it looks like i change an utf8-string to an utf8-string.
>

There's no such thing as a UTF-8 string. You have a list of bytes
(byte string) and you have a list of characters (unicode). UTF-8 is a
function that can convert bytes into characters (and the reverse). You
may recognize that the list of bytes was encoded using UTF-8 but the
computer does not unless you explicitly tell it to. Does that help
clear it up?