BUG: RFX_DATE() May Use Incorrect Precision Value (122218)
The information in this article applies to:
- The Microsoft Foundation Classes (MFC), when used with:
- Microsoft Visual C++ for Windows, 16-bit edition 1.5
- Microsoft Visual C++ for Windows, 16-bit edition 1.51
- Microsoft Visual C++, 32-bit Editions 2.0
- Microsoft Visual C++, 32-bit Editions 2.1
- Microsoft Visual C++, 32-bit Editions 4.0
- Microsoft Visual C++, 32-bit Editions 4.1
- Microsoft Visual C++, 32-bit Editions 4.2
- Microsoft Visual C++, 32-bit Editions 4.2b
- Microsoft Visual C++, 32-bit Editions 5.0
- Microsoft Visual C++, 32-bit Editions 6.0
- Microsoft Visual C++ .NET (2002)
- Microsoft Visual C++ .NET (2003)
This article was previously published under Q122218 SYMPTOMS
Using the RFX_Date() functions in the Microsoft Foundation Classes fails to
work with date/time fields with some ODBC drivers. A general ODBC error or
'invalid precision' error may occur depending upon the ODBC driver.
CAUSE
RFX_Date() calls SQLSetParam() and SQLBindCol() with a precision parameter
equal to 23 (sizeof TIMESTAMP_STRUCT). Some ODBC drivers may not use the
same precision for a SQL_TIMESTAMP. For example, some ODBC drivers may
choose ignore seconds or fractions of a second; in these cases, the
precision may be smaller.
RESOLUTION
To work around this problem, you must re-write the RFX_Date() function
and call your new function in your CRecordset's DoFieldExchange(),
replacing the RFX_Date() call.
In your new RFX_Date() function you will need to: - Get the precision of a SQL_TIMESTAMP column by using the
ODBC function SQLGetTypeInfo() for the data source connected
to by the CRecordset.
- Store the precision value in a variable in your recordset so
that you can retrieve it later.
- Replace all references of TIMESTAMP_PRECISION in your RFX_Date()
function with a reference to the precision variable contained in
your CRecordset class.
STATUS
Microsoft has confirmed this to be a bug in the Microsoft products listed
at the beginning of this article. We are researching this bug and will post
new information here in the Microsoft Knowledge Base as it becomes
available.
| Modification Type: | Major | Last Reviewed: | 12/9/2003 |
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| Keywords: | kbBug KB122218 |
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