DOCUMENT:Q181480 17-JUL-2001 [visualc] TITLE :FIX: MFC ODBC Cannot Update Access Date/Time with No Date PRODUCT :Microsoft C Compiler PROD/VER::2.5,2000,5.0,6.0,97 OPER/SYS: KEYWORDS:kbJET kbMFC kbODBC kbVC500 kbVC600 kbGrpDSVCDB kbGrpDSMDAC kbDSupport MSGRAPH kbMDAC250 ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - The Microsoft Foundation Classes (MFC), used with: - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 - Microsoft Visual C++, 32-bit Enterprise Edition, version 6.0 - Microsoft Visual C++, 32-bit Professional Edition, version 6.0 - Microsoft Visual C++, 32-bit Learning Edition, version 6.0 - Microsoft Access 2000 - Microsoft Data Access Components version 2.5 ------------------------------------------------------------------------------- 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 : kbJET kbMFC kbODBC kbVC500 kbVC600 kbGrpDSVCDB kbGrpDSMDAC kbDSupport MSGRAPH kbMDAC250 kbMDAC260fix kbMDACNoSweep Technology : kbAudDeveloper kbMFC Version : :2.5,2000,5.0,6.0,97 Issue type : kbbug Solution Type : kbfix ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.