FIX: MFC ODBC Cannot Update Access Date/Time with No Date
Article ID: 181480
Article Last Modified on 11/21/2006
APPLIES TO
- Microsoft Foundation Class Library 4.2, when used with:
- Microsoft Visual C++ 5.0 Enterprise Edition
- Microsoft Visual C++ 5.0 Professional Edition
- Microsoft Visual C++ 6.0 Enterprise Edition
- Microsoft Visual C++ 6.0 Professional Edition
- Microsoft Visual C++ 6.0 Standard Edition
- Microsoft Access 2000 Standard Edition
- Microsoft Data Access Components 2.5
This article was previously published under Q181480
SYMPTOMS
When you update records in an Access database using the ODBC cursor library
and you previously added a date/time field in Access without a date using
the CRecordset (with TIMESTAMP_STRUCT) classes, MFC throws the following
exception:
No Rows Affected
CAUSE
The ODBC WHERE clause fails to find the record it needs to update it.
RESOLUTION
This problem has been fixed in MDAC 2.6. For MDAC versions before 2.6 use the following workarounds:
You must always enter a date in the Access date/time field for CRecordset
classes using the ODBC cursor library.
You can also resolve this problem by switching to dynasets.
STATUS
MORE INFORMATION
If you have to use the ODBC cursor library, you must always enter a date
along with a time in the Access date/time field. If you only enter a time,
the recordset will fail to post updates and the MFC exception "No Rows
Affected" will be thrown. This occurs because the ODBC cursor library
attempts to update the database using an UPDATE clause and attempts to
select all columns to ensure a unique record. During this selection, the
date field fails to be resolved.
If you do not have to use the ODBC cursor library, you can open the
recordset as a dynaset, which effectively eliminates this problem.
REFERENCES
Visual C++, Microsoft Foundation Class Reference, Class Library Reference:
Crecordset; CDatabase
Additional query words: MfcDatabase
Keywords: kbbug kbfix kbjet kbmdac260fix kbmdacnosweep KB181480