Re: SQLGetData() returns len 4095 for empty TEXT on AIX 6.1 without ClientCharset defined

Have you tried this with a newer FreeTDS version ??

It works for me. Unexpectedly it returns data even after a
SQLMoreResults. Did you try with MS drivers?

Frediano


2013/3/18 Sebastien FLAESCH <[email protected]>:
> Ok, once again ;-)
>
> Attached the little sample to reproduce.
>
> I fact, I use column-wise binding, but when LOB columns need to be
> fetched, I use an array size of 1. It may look strange, but I have
> to write generic code, to execute SQL statements that are not known
> at compile time.
>
> Compilation command used:
>
> xlc -O2 -qmaxmem=8192 -q64 -I/dbs/64bits/uxo/2.3.1/include
>     -o odbctest2.bin odbctest2.c
>     -L/dbs/64bits/tds/0.83/lib -ltdsodbc
>

I think you keep 0.83 for compatibility.

>
> ODBC source:
>
> [ftm_msvtest1_cobra]
> Description     = SQL Server 2012
> Trace           = No
> Server          = cobra
> Database        = msvtest1
> Port            = 1680
> TDS_Version     = 8.0
>

You can use 7.1 here.

>
>
> Output on the Linux 32b machine:
>
> num cols: 2
> fetch 1: rows fetched = 1
> get data 1: len = 0
>
> Output on the AIX 6.1 machine:
>
> num cols: 2
> fetch 1: rows fetched = 1
> get data 1: len = 4095
>
>
> Maybe this can help:
>
> When I set a (valid) ClientCharset like ISO8859-15 or UTF-8, I get the
> unexpected length of 4095, but with an invalid ClientCharset, I get zero.
>
> !!! The length returned by SQLGetData() is in fact the size of the buffer
> provided, minus one...
>
>
> (sorry for the confusion)
> Seb
>
>
>
> On 03/18/2013 10:25 AM, Sebastien FLAESCH wrote:
>>
>> Sorry:
>>
>> After a closer look I don't use column-wise binding if a text/byte
>> column is in the result set.
>>
>> Seb
>>
>> On 03/18/2013 10:04 AM, Sebastien FLAESCH wrote:
>>>
>>> OK.
>>>
>>> FYI, I am using column-wise binding with:
>>>
>>>        rcode = SQLSetStmtAttr(m_hstmt_2, SQL_ATTR_ROW_BIND_TYPE,
>>>                               (SQLPOINTER) SQL_BIND_BY_COLUMN,
>>> SQL_IS_UINTEGER);
>>>
>>>        rcode = SQLSetStmtAttr(m_hstmt_2, SQL_ATTR_ROW_ARRAY_SIZE,
>>>                               (SQLPOINTER) ARRAY_SIZE, SQL_IS_UINTEGER);
>>>
>>>        rcode = SQLSetStmtAttr(m_hstmt_2, SQL_ATTR_ROWS_FETCHED_PTR,
>>>                               (SQLPOINTER)&   (nrows), SQL_IS_UINTEGER);
>>>
>>> I will try to reproduce with a small sample.
>>>
>>> Seb
>>>
>>> On 03/16/2013 03:04 PM, Frediano Ziglio wrote:
>>>>
>>>> 2013/3/14 Sebastien FLAESCH<[email protected]>:
>>>>>
>>>>> Hi,
>>>>>
>>>>> I have already reported an issue regarding SQLGetData()/iconv, see
>>>>> mails with title:
>>>>>
>>>>> "SQLGetData() returns TEXT length minus one on Solaris 64b with SQL
>>>>> Server 2005"
>>>>>
>>>>> But now we have a similar problem on AIX 6.1, still with version
>>>>> 0.92.377.
>>>>>
>>>>> After inserting an empty TEXT, we fetch it back (see mail history for
>>>>> details),
>>>>> and SQLGetData() returns a len of 4095 bytes, when zero is expected.
>>>>>
>>>>
>>>> I downloaded 0.92.377, forced indirect conversion and checked
>>>> SQLGetData with empty text (there is also a spcific test in getdata
>>>> test but I enhanced it) but unfortunately was not able to reproduce
>>>> your result (getting 4095 for an empty string). Could you help repro
>>>> the case? Or I didn't understand your problem?
>>>>
>>>>> This occurs if no ClientCharset is defined in the ODBC data source...
>>>>>
>>>>> When setting:
>>>>>
>>>>>        ClientCharset = en_US.8859-15
>>>>>
>>>>> or:
>>>>>
>>>>>        ClientCharset = en_US.UTF-8
>>>>>
>>>>> The len returned by SQLGetData() is zero, as expected.
>>>>>
>>>>> Some news about this?
>>>>>
>>>>> As I suggested, if there is some iconv conversion issues, FreeTDS
>>>>> should stop
>>>>> with a fatal error, to avoid any data loss / mis-conversion. It should
>>>>> not
>>>>> silently send or return invalid character data.
>>>>>
>>>>> Seb
>>>>>
>>>>>
>>>>
>>>> Mmm... from my log
>>>>
>>>> 13:44:19.515397 (token.c:321):looking for login token, got  ad(LOGINACK)
>>>> 13:44:19.515401 (token.c:357):server reports TDS version 71.0.0.1
>>>> 13:44:19.515404 (token.c:359):Product name for 0x71000001 is 2000 SP1
>>>> 13:44:19.515409 (token.c:391):Product version 89001388
>>>> 13:44:19.515413 (token.c:321):looking for login token, got
>>>> e3(ENVCHANGE)
>>>> 13:44:19.515417 (token.c:107):tds_process_default_tokens() marker is
>>>> e3(ENVCHANGE)
>>>> 13:44:19.515422 (token.c:2045):changing block size from 4096 to 4096
>>>> 13:44:19.515426 (token.c:321):looking for login token, got  fd(DONE)
>>>> 13:44:19.515430 (token.c:107):tds_process_default_tokens() marker is
>>>> fd(DONE)
>>>> 13:44:19.515435 (token.c:1905):tds_process_end: more_results = 0
>>>>                    was_cancelled = 0
>>>>                    error = 0
>>>>                    done_count_valid = 0
>>>> 13:44:19.515440 (token.c:1921):                rows_affected = 0
>>>> 13:44:19.515443 (token.c:1924):tds_process_end() state set to TDS_IDLE
>>>> 13:44:19.515448 (token.c:423):tds_process_login_tokens() returning
>>>> TDS_SUCCESS
>>>> 13:44:19.515467 (iconv.c:967):tds_iconv_get: what is charset
>>>> "en_US.8859-15"?
>>>> 13:44:19.515475 (odbc.c:1723):SQLAllocStmt(0x207f380, 0x606de0)
>>>> 13:44:19.515479 (odbc.c:1621):_SQLAllocStmt(0x207f380, 0x606de0)
>>>>
>>>>
>>>> As you reported another charset is silently used. Also strangely seems
>>>> that client charset is readed after the login. Oh, probably cause is
>>>> used only to convert data as now wide is the default and UTF-8 is used
>>>> in libTDS. Yes, that is, disabling wide cause connection to fail using
>>>> an invalid charset! So this is a regression of wide support in odbc.
>>>>
>>>> Frediano