INFO: Changes in ADO 1.5 That Affect Visual C++/J++ Programmers

ID: Q177939

The information in this article applies to:

ActiveX Data Objects (ADO), version 1.5
Microsoft Visual C++, 32-bit Editions, versions 4.2b, 5.0, 6.0
Microsoft Visual J++, versions 1.0, 1.1, 6.0

SUMMARY

With the release of ActiveX Data Objects (ADO) version 1.5, several minor changes have been made that may affect code when recompiled to use ADO 1.5 for Visual C++ or Visual J++. This article outlines the changes and the steps you need to take to compensate for the changes. Not all of the changes affect both Visual C++ and Visual J++; this article indicates which issues are language specific.

MORE INFORMATION

Adoid.lib No Longer Exists (Visual C++ - Only)

With the release of the OLE DB 1.5 Software Development Kit (SDK), Microsoft no longer provides the Adoid.lib file. Instead, to link to ADO 1.5, use the code snippet below. This code snippet assumes you are not using #import or Microsoft Foundation Classes (MFC) OLE to link to ADO. If you are using #import or MFC-OLE the #include to <initguid.h> is not necessary.


   #include <initguid.h>    // Newly Required for ADO 1.5.
   #include <adoid.h>
   #include <adoint.h>

You must also remove linking to the Adoid.lib in your Project's Settings dialog box or you will continue to link to ADO 1.0. If you get the following error after you remove Adoid.lib, you must define INITGUID (using #define INITGUID) on the first line of your .cpp file:


   LNK2001: unresolved external symbol _CLSID_CADORecordset

NOTE: You must install the OLE DB 1.5 Software Development Kit (SDK) to obtain the latest versions of Adoid.h and Adoint.h.

The OLE DB SDK version 1.5 released in January 1998 and is available at the following address:

http://www.microsoft.com/data/oledb

You may also receive the following error if you build a project linking to the 1.0 Adoid.lib and including the 1.5 Headers:

LNK2005: "xxx" already defined in "yyy" errors

From the Projects menu, choose Settings, select the Link tab, and remove the reference to the Adoid.lib file.

Create a new file in the project called Oleguids.cpp and add these lines:


      #include <initguid.h>
      #include <adoid.h>
      #include <adoint.h>

Compile and Link.

The OLE DB 1.5 SDK does not remove Adoid.lib from the oledbsdk\lib directory. You may want to physically delete it after installing the 1.5 SDK to ensure that no conflicts occur in the future.

Extra Argument in Connection.Open() Method (Visual C++ and Visual J++)

A new, reserved Options parameter was added to the Connection.Open() method. You must use a value of -1 for this argument as shown in the following code snippets. Unlike other arguments for ActiveX Data Objects (ADO), the new Options argument does not have an enumerated type within the typelib to indicate valid values.


   
// VC using #import
  Conn1->Open( bstrEmpty, bstrEmpty, bstrEmpty, -1 );

// VC using MFC OLE
  Conn1.Open( strEmpty, strEmpty, strEmpty, -1 );

// VC Using OLE SDK
   if( SUCCEEDED( hr ) )
   hr = Conn1->Open( bstrEmpty, bstrEmpty, bstrEmpty, -1 );

// Java Code
  conn1.Open("", "", "", -1);

If you use the incorrect value for this argument, the following error occurs:

800A0BB9 or (adErrInvalidArgument = 3001)

The application is using arguments that are of the wrong type, are out of acceptable range, or are in conflict with one another.

Extra Argument in Recordset.Requery() Method (Visual C++ and Visual J++)

As with the Connection.Open() method, the Recordset.Requery method now also has a reserved parameter, whose value must be set to -1. Failure to do so generates the same error listed above (0x800A0BB9).

REFERENCES

For additional information, please see the following articles in the Microsoft Knowledge Base:

Q130869 HOWTO: Avoid Error LNK2001 Unresolved External Using DEFINE_GUID

Q182389 FILE: Adovcbm.exe ADO 1.5 with #import and Getrows/Bookmarks

Q184968 FILE: Adovcsp.exe Demonstrates Using Stored Procedures with ADO

Q186387 SAMPLE: Ado2atl.exe Returns ADO Interfaces from COM

Q181733 FILE: Adovcbtd.exe #import Using UpdateBatch and CancelBatch

Additional query words: Parameter Arguments Differences kbdse

Keywords : kbADO kbDatabase kbVC kbVJ kbGrpVCDB kbGrpMDAC
Version : WINDOWS:1.0,1.1,1.5,6.0; winnt:4.2b,5.0,6.0
Platform : WINDOWS winnt
Issue type : kbinfo