BUG: SQLParamData Returns Incorrect Values Under Win32s (135715)



The information in this article applies to:

  • Microsoft Open Database Connectivity

This article was previously published under Q135715
BUG#: 3160 (ODBCSDK2 2.10b)

SYMPTOMS

When you run a 32-bit ODBC application under Win32s, the SQLParamData function returns incorrect values for the prgbValue argument.

STATUS

Microsoft has confirmed this to be a problem in the Win32s ODBC thunking components. We are researching this problem and will post new information here in the Microsoft KnowledgeBase as it becomes available.

MORE INFORMATION

SQLParamData is an ODBC API call that is used in conjunction with SQLPutData to supply parameter data at statement execution time. This call is made to retrieve the application-defined value specified in the rgbValue argument of SQLBindParameter for the data-at-execution parameter to be processed.

The following 32-bit Windows program demonstrates the problem. In this program, the rgbValue buffer of SQLBindParameter contains a number Ideally, when SQLParamData is called subsequently, the prgbValue buffer should return the same number. However, a number such as 3a175678 is returned.

If you create the appropriate data source and run the following program under Windows NT, you will get two message boxes that each contain the same number (12345678). If you create the appropriate data source and run it under Win32s, you will get two message boxes that contain different numbers (12345678 and something like 3a175678). The first number is the rgbValue parameter in the call to SQLBindParameter(). The second number is the value returned through the prgbValue parameter in the call to SQLParamData().

EXAMPLE PROGRAM:
/*
  To run this program, create and Access ODBC data source named
"BLOBTEST1".

  The data source should contain a table named "Table1" that contains 2
  fields, a short field named "Field1" and a long binary field named
"Field2"
.
*/ 

#include <windows.h>
#include <sql.h>
#include <sqlext.h>
#include <stdio.h>


HENV   henv;
HDBC   hdbc;
HSTMT   hstmt;

long      id = 0x12345678;
PTR      ret_id;
SDWORD   length;
RETCODE   retcode;
char      buffer[200];

int PASCAL WinMain(HINSTANCE hinst,HINSTANCE pinst,LPSTR szCmd,int nShow)
{
  if (SQLAllocEnv(&henv) != SQL_SUCCESS)
  {

    MessageBox(NULL,"SQLAllocEnv() failed","Error",MB_ICONSTOP);
    goto Out1;
  }

  if (SQLAllocConnect(henv,&hdbc) != SQL_SUCCESS)
  {
    MessageBox(NULL,"SQLAllocConnect() failed","Error",MB_ICONSTOP);
    goto Out2;

  }

  if (SQLConnect(hdbc,"BLOBTEST1",SQL_NTS,"",SQL_NTS,"",SQL_NTS) !=
SQL_SUCCESS)
  {
    MessageBox(NULL,"SQLConnect() failed","Error",MB_ICONSTOP);
    goto Out3;
  }

  if (SQLAllocStmt(hdbc,&hstmt) != SQL_SUCCESS)
  {
    MessageBox(NULL,"SQLAllocStmt() failed","Error",MB_ICONSTOP);
    goto Out4;
  }

  if (SQLPrepare(hstmt,"INSERT INTO Table1 (Field1,Field2) values
(1,?)",SQL_NTS) != SQL_SUCCESS)
  {
    MessageBox(NULL,"SQLPrepare() failed","Error",MB_ICONSTOP);
    goto Out5;
  }

  sprintf(buffer,"Calling SQLBindParameter, value = %x\n",id);
  MessageBox(NULL,buffer,"Info",MB_OK);
  if
(SQLBindParameter(hstmt,1,SQL_PARAM_INPUT,SQL_C_BINARY,SQL_LONGVARBINA
Y,0,0,(PTR)id,0,&length)
   != SQL_SUCCESS)
  {
    MessageBox(NULL,"SQLBindParameter() failed","Error",MB_ICONSTOP);
    goto Out5;
  }

  length = SQL_LEN_DATA_AT_EXEC(0);
  retcode = SQLExecute(hstmt);
  while (retcode == SQL_NEED_DATA)
  {
    retcode = SQLParamData(hstmt,&ret_id);
    if (retcode == SQL_NEED_DATA)
    {
      sprintf(buffer,"Returned value = %x\n",(long)ret_id);
      MessageBox(NULL,buffer,"Info",MB_OK);      //Expected
display: 12345678. But, something like 3a175678 is displayed.
      SQLPutData(hstmt,"1234567890",10);      // just send
some data..
    }
  }

Out5:
  SQLFreeStmt(hstmt,SQL_DROP);
Out4:
  SQLDisconnect(hdbc);
Out3:
  SQLFreeConnect(hdbc);
Out2:
  SQLFreeEnv(henv);
Out1:
  return 0;
}
				

Modification Type:MajorLast Reviewed:12/2/2002
Keywords:kbBug KB135715 kbAudDeveloper