The information in this article applies to:
SUMMARYJet is the default database engine for Visual Basic as well as other Microsoft applications such as Microsoft Access, Microsoft Excel, Project, and Microsoft Foundation Classes (MFC). Which version of Jet you are using can be unclear because Visual Basic and other applications using Jet are continually being updated. The tables and explanations in this article are intended to help you identify the version and components of Jet that you are using for the given application. MORE INFORMATIONThe list below displays which version of Jet is shipped with each of the following products:
Compatibility Among VersionsWith each new version of Microsoft Jet, enhancements in functionality and changes to the structure of the database file cause problems with backward compatibility. Wherever possible, efforts have been made to ensure an easy migration path among versions. However, incompatibilities do exist. The following table illustrates how database files and objects can be used among different versions of Microsoft Jet.
A "Y" indicates that the database can be used without conversion; "N"
indicates that the database cannot be used or converted. With DAO code you
can open any version of any database up to the same version of Microsoft
Jet. However, Microsoft Access can open only those databases with the same
version as itself, but it can link to tables with the same or earlier
version. In other words, if you upgrade to Microsoft Jet 3.0, you will
still be able to read version 2.x databases.
Notice that Visual Basic 3.0 is capable of using three different versions of Jet each requiring a separate set of dynamic link libraries (.dlls). This can cause problems when your Visual Basic application expects to use Jet 2.0 for example, and then another Visual Basic application using an earlier version of Jet gets installed on the same system replacing some of the version 2.0 .dlls with version 1.1. Typically the problem .dll in this situation is VBDB300.DLL because it determines which version of the Jet engine will be used. The following table should help you solve any version conflicts and help you identify the version of Jet you are using. You may use the Wps.exe utility shipped with Visual Basic to find out which version of Jet you currently have loaded in memory. Wps.exe is located in the \VB\CDK directory of Visual Basic 3.0 Professional, and in \TOOLS\PSS directory of the Visual Basic 4.0 CD. Pay special attention to the version information obtained from File Manager (File, Properties) in Visual Basic 3.0, and Microsoft System Info. in Visual Basic 4.0 32-bit. The following files are required by Visual Basic to use the Jet Database Engine:
The Visual Basic Compatibility Layer (Comlyr.exe) and the Microsoft Access
Service Pack (Accsvc.exe) are available for download from the Microsoft
Software Library:
The following files are available for download from the Microsoft
Software Library. Click the file names below to download the files:Comlyr.exe Accsvc.exeRelease Date: August 15, 1999 For more information about how to download files from the Microsoft Software Library, please see the following article in the Microsoft Knowledge Base: Q119591 How to Obtain Microsoft Support Files from Online Services REFERENCESMicrosoft Jet Database Engine Programmer's Guide, by Dan Haught and Jim Ferguson, Microsoft Press 1995 For additional information, please click the article numbers below to view the articles in the Microsoft Knowledge Base: Q113683 FILE: Fact Sheet on Jet 2.0/VB 3.0 Compatibility Layer Q122927 WX1124: Microsoft Access Version 2.0 Service Pack Q172733 Updated Version of Microsoft Jet 3.5 Available on MSL Additional query words:
Keywords : kbfile kbsample kbMFC kbVBp400 kbVBp500 kbVBp600 |
Last Reviewed: October 13, 1999 © 2000 Microsoft Corporation. All rights reserved. Terms of Use. |