ERROR 'utf-8' codec can't decode byte 0x85 in position 0: invalid start byte

[bnvader]

I am trying to use python oracledb to connect to Oracle Database that has encoding - ISO-8859-1.
I have a custom database type of type DB Table.
When I use thick client mode, I am able to directly use the DBObject.Attribute_Name to retrieve the attribute values from a row.
However this same step fails if I do not use thick mode.

I would like to have this working in thin mode as I want to eventually use this from a simple AWS Lambda function.

Has anyone been able to use thin mode to successfully decode non utf-8 encoded Oracle DB?
If so what is the secret?

[anthony-tuininga]

The first step is to confirm what the database character set actually is: https://python-oracledb.readthedocs.io/en/latest/user_guide/globalization.html#database-character-set. Once you confirm this, can you supply it here along with the DDL required to create the object type and the Python code you are using to access it?

If the data stored in the database actually follows this character set, then conversion to AL32UTF8 (utf-8) is automatic and will not result in errors. It is, however, quite possible for the client and server to specify the SAME character set and then the server doesn't perform any conversions or checks. In that case the client can store corrupt data without any errors being raised! If that is the case you can use this technique to work around it: https://python-oracledb.readthedocs.io/en/latest/user_guide/sql_execution.html#querying-corrupt-data.

[bnvader]

There is an XML type column in this. I m pretty sure that is the one causing the issue.
Even in thick mode, I was not able to retrieve that column and needed to write a separate select sql to retrieve it separately.
"select xmltype.getclobval(USER_DATA) from ebp.transaction where trans_id = " + str(trans_id)

[bnvader]

With thick client -
print(resultobj.USER_DATA)
File ~\AppData\Local\anaconda3\Lib\site-packages\oracledb\dbobject.py:47 in getattr
return self._impl.get_attr_value(attr_impl)
File src\oracledb\impl/thick/dbobject.pyx:113 in oracledb.thick_impl.ThickDbObjectImpl.get_attr_value
File src\oracledb\impl/thick/utils.pyx:450 in oracledb.thick_impl._raise_from_odpi
File src\oracledb\impl/thick/utils.pyx:440 in oracledb.thick_impl._raise_from_info
DatabaseError: DPI-1008: data type 58 is not supported

[anthony-tuininga]

Thanks. I can replicate now and have created issue #336 to track this.

[bnvader]

Thank, appreciate it.

[anthony-tuininga]

A patch is available, @bnvader. See #336 for details.