| Bug #29871 | MyODBC problem with MS Query ('Memory allocation error') | ||
|---|---|---|---|
| Submitted: | 18 Jul 2007 15:41 | Modified: | 26 Feb 2008 12:21 |
| Reporter: | Bogdan Degtyariov | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | Connector / ODBC | Severity: | S2 (Serious) |
| Version: | 3.51.16, 3.51.17 | OS: | Any |
| Assigned to: | Bogdan Degtyariov | CPU Architecture: | Any |
| Tags: | Excel, MyODBC, query | ||
[15 Aug 2007 10:06]
Bogdan Degtyariov
Trying to narrow the problem to a C test case
[15 Aug 2007 12:47]
Bogdan Degtyariov
I found out that MSQuery binds the query parameters in an unusual way. It mostly affects integer columns. The value type is SQL_C_CHAR whereas the parameter type is SQL_INTEGER. This causes misinterpretation of the parameter when inserting it into the resulting SQL query.
[15 Aug 2007 15:36]
Bogdan Degtyariov
parameter length -1 appeared due to use of a deprecated function SQLSetParam instead of SQLBindParam. I wonder why it is mapped so, that SQLBindParam is being called with SQL_SETPARAM_VALUE_MAX (-1L) whereas the direct call of SQLBindParam with this option fails: [ HY090] [Microsoft][ODBC Driver Manager] Invalid string or buffer length
[15 Aug 2007 16:33]
Bogdan Degtyariov
Patch and test case
Attachment: patch29871.diff (application/octet-stream, text), 1.85 KiB.
[30 Aug 2007 15:55]
Jim Winstead
change if ( length > param->ValueMax && param->ValueMax > 0 ) to if (length != SQL_SETPARAM_VALUE_MAX && length > param->ValueMax) and fix the formatting of the comment preceding this line. okay to push.
[13 Sep 2007 11:02]
Bogdan Degtyariov
The following condition does not work for MS Query: if (length != SQL_SETPARAM_VALUE_MAX && length > param->ValueMax) it has to be changed to: if (param->ValueMax != SQL_SETPARAM_VALUE_MAX && length > param->ValueMax)
[13 Sep 2007 11:36]
MC Brown
A note has been added to the 3.51.20 changelog: SQLSetParam() caused memory allocation errors due to driver manager's mapping of deprecated functions (buffer length -1).
[21 Sep 2007 17:51]
Bogdan Degtyariov
New patch incuding SQLSetParam function (mapped to SQLBindParameter)
Attachment: patch29871v2.diff (application/octet-stream, text), 2.71 KiB.
[22 Sep 2007 8:08]
Jim Winstead
the comment should be written in doxygen-style, and some of the code formatting fixed, but the code looks fine.
[4 Oct 2007 21:01]
Jim Winstead
The fix for this bug was committed to the source repository, and will be in 3.51.21.
[12 Oct 2007 13:12]
MC Brown
A note has been added to the 3.51.21 changelog: SQLSetParam() caused memory allocation errors due to driver manager's mapping of deprecated functions (buffer length -1).
[2 Feb 2008 3:08]
Jess Balint
The test for this bug is failing. The function is not exported (I checked 3.51.23 release DLL). SQLSetPos() needs to be exported. Also, the test-case should verify that the correct data was inserted.
[2 Feb 2008 3:08]
Jess Balint
Sorry, SQLSetParam() needs to be exported.
[7 Feb 2008 16:52]
Bogdan Degtyariov
New version of the patch
Attachment: patch29871v6.diff (application/octet-stream, text), 2.27 KiB.
[26 Feb 2008 12:21]
MC Brown
The existing changelog entry has also been tagged against the 3.51.24 release.
Description: The problem appears in MS Query when trying to import the data into Excel. How to repeat: Open MS excel > Data > new database query >pick up the DSN just configed and pick up some tables > View data or edit query in Microsoft Query > Allow editing > Modify some data field and try to return data to Excel. Suggested fix: When MS Query uses parameters in queries MyODBC incorrectly calculates the size of the buffer as: if ( length > param->ValueMax ) length = param->ValueMax; for ValueMax == -1 the length cannot be considered as valid. To fix the problem it is necessary to add a new condition: if ( length > param->ValueMax && param->ValueMax > 0) length = param->ValueMax;