FIX: Problems When Using an Oracle Data Source (112757)
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++ for Windows, 16-bit edition 1.52
- Microsoft Visual C++, 32-bit Editions 2.2
This article was previously published under Q112757 SYMPTOMS
An application built to access an Oracle data source using the Microsoft
Foundation Classes (MFC) may crash or throw a CDBException exception or
generate oracle error ora-02019.
CAUSE
Two known Oracle-driver-specific problems are:
- AppWizard and ClassWizard generate an incorrect GetDefaultSQL() function
for an Oracle data source table.
- A stack overflow may occur when connecting to an Oracle data source.
(This behavior is specific to 16-bit applications.)
RESOLUTION
There is a bug in the wizards that causes them to generate an incorrect
GetDefaultSQL() function when using an Oracle data source. Looking at the
CRecordset's GetDefaultSQL() function you will see that an at sign ("@")
has been placed between the table owner and the table name. For example,
you may see:
CString CMyRecordSet::GetDefaultSQL()
{
return "Dan@Customer";
}
Change the "@" to a period (.).
An application may also crash because of a stack overflow. The Oracle
drivers use a large amount of stack space. If the stack overflows, it will
write into the main data segment and cause undefined behavior after
returning to the application. This may be resolved by increasing the stack
size of your application.
STATUS
Microsoft has confirmed this to be a bug in the Microsoft products
listed at the beginning of this article. This bug was corrected in
Microsoft Visual C++, 32-bit Edition, version 4.0
| Modification Type: | Major | Last Reviewed: | 12/2/2003 |
|---|
| Keywords: | kbbug kbDatabase kbfix KB112757 |
|---|
|