Re: Teradata using DBD::ODBC
"Martin J. Evans" <[email protected]>
| Newsgroups | gmane.comp.lang.perl.modules.dbi.general |
|---|---|
| Message-ID | <[email protected]> |
On 22/11/2011 18:57, Martin J. Evans wrote:
> On 22/11/2011 08:48, Martin J. Evans wrote:
>> On 21/11/11 18:51, Yang, Longjiang wrote:
>>> Hi,
>>>
>>>
>>>
>>> I use DBD::ODBC to connect to Teradata. I need to get column data type
>>> back. when using $sth->{TYPE}. I got IDs not in $dbh->type_info_all. It
>>> appears to happen to only CHAR and VARCHAR types. Does anyone know how
>>> to get the data type information for a column (in a query)? Thanks.
>>>
>>>
>>>
>>> Here is the code. Note that -8 in $sth->{TYPE} is not defined in
>>> $dbh->type_info_all. It is the ID for both CHAR and VARCHAR columns
>>> defined in the table. I tried the same using DBD::ADO and got similar
>>> issue.
>>>
>>
>> type_info_all calls ODBC's SQLGetTypeInfo and the ODBC driver returns
>> the result-set. {TYPE} returns the type returned from SQLDescribeCol.
>> You are obviously on Windows where DBD::ODBC builds in Unicode mode
>> by default. This causes DBD::ODBC to call SQLDescribeColW (the wide
>> version of SQLDescribeCol) and in this case the driver will mostly
>> return -8 (SQL_WCHAR) from char columns. However, DBD::ODBC does not
>> yet call SQLGetTypeInfoW and hence the difference. Arguably, it is a
>> bug in DBD::ODBC so by all means report it at rt.cpan.org and I will
>> fix it as I am working in that area right now.
>>
>> <snipped test code>
>>
>> If you are in a position to rebuild a new DBD::ODBC and test the fix
>> that will influence how quickly I get around to making the change.
>>
>> Martin
>
> In actual fact if you download DBD::ODBC 1.32_3 this version calls
> SQLTablesW in a unicode build so you should try that. Get back to me
> if you find any issues.
>
> Be aware I've not done column_info completely for Unicode yet (and the
> other metadata methods like primary_keys) but I'm working on it right
> now.
>
> Martin
OOPs forget that - it was SQLGetTypeInfo not SQLTables.
Sorry, I will work on SQLGetTypeInfo tonight.
Martin