SQLAlchemy 使用 utf8 转换字段

Question

如何获得此 SQL 查询的等效 SQLAlchemy 语句？

select CONVERT(blobby USING utf8) as blobby from myTable where CONVERT(blobby USING utf8)="Hello";

其中 blobby 是一个 blob 类型的字段，必须将其分解为字符串。

我试过了

DBSession.query(myTable).filter(myTable.blobby.encode(utf-8)="Hello").first()

但不起作用。给出一个奇怪的错误

AttributeError: Neither 'InstrumentedAttribute' object nor 'Comparator' object associated with myTable.blobby has an attribute 'encode'

此外，我尝试如下插入数据库：

que=myTable(blobby=str(x.blobby))
DBSession.add(que)

这也会返回一个错误提示

(ProgrammingError) You must not use 8-bit bytestrings unless you use a text_factory that can interpret 8-bit bytestrings (like text_factory = str). It is highly recommended that you instead just switch your application to Unicode strings.

如果我像这样插入，这个错误就会消失

que=myTable(blobby=str(x))

但是插入的条目不支持外语值..

 EDIT:-

这就是我想要做的：

I have a list of utf-8 strings. The sqlalchemy column which I am
trying to insert my string has the property "convert_unicode" set to
true. Now, I have to insert these strings into my database without
loss of data. I need to preserve my multilingual characters which
worked fine when I fetched them as utf-8 from my Mysql database.
Trouble here is inserting them into SQLite using SQLalchemy.

请帮忙。谢谢和问候。

Answer 1

这就是我为摆脱编码地狱和这个错误所做的事情。

UnicodeDecodeError: 'ascii' codec
can't decode byte 0xc4 in position
10: ordinal not in range(128)

我会逐步解释。

1. 使用此命令：type(mydirtyunicodestring)。

2. 如果返回 那么这意味着您必须将其转换为 unicode 才能获得 摆脱错误。（字节字符串！！！！）

3. 使用dirtystring.decode('utf-8') 或任何其他格式让您的类型出现在您那里 走。不会再出现 8 位编程错误 ProgrammingError) You must not use 8-bit bytestrings unless you use a text_factory that can interpret 8-bit bytestrings (like text_factory = str).