Saving Your Database as an MDE File

If you are using Microsoft Access 97 and your primary security concern is protecting the design of your forms, reports, and modules, you can save your database as an MDE file instead of using user-level security. You can also save a database as an MDE file in conjunction with using other forms of security.

Saving your database as an MDE file creates a separate copy of your database that contains no Visual Basic source code and is smaller than the original database. Your code is compiled and continues to run, but it can’t be viewed or edited. Additionally, users can’t view or modify the design of forms, reports, and modules in an MDE database. However, users can view and modify the relationships and the design of tables, queries, and macros in an MDE database.

Saving your database as an MDE file also prevents the following actions:

• Creating forms, reports, or modules.
  
  
• Adding or deleting references to object libraries or databases by using the References command on the Tools menu.
  
  
• Using the Object Browser.
  
  
• Changing code by using the properties or methods of the Microsoft Access or Visual Basic object models (because an MDE file contains no source code).
  
  
• Importing or exporting forms, reports, or modules. However, tables, queries, and macros can be imported from or exported to non-MDE databases. Any tables, queries, or macros in an MDE database can be imported into another database, but no forms, reports, or modules can be imported into another database.

If you need to modify the design of forms, reports, or modules in a database saved as an MDE file, you must open the original non-MDE database, modify it, and then save it as an MDE file again. Saving a database that contains tables as an MDE file creates complications reconciling different versions of the data if you need to modify the design of the application later. For this reason, saving a database as an MDE file is most appropriate for the front end of an application that has been split into a front-end/back-end database, in which the back end contains only tables and the front end contains the remaining objects.

See Also For more information about splitting databases, see “The Two-Database Approach” in Chapter 6, “Creating Multiuser Applications.”

Note The process of saving a database as an MDE file compiles all modules and compacts the destination database, so there is no need to perform these steps before saving a database as an MDE file.

Û To save a database as an MDE file

1. Close the database. If the database is being shared on a network, make sure no other users have it open.
   
   
2. On the Tools menu, point to Database Utilities, and then click Make MDE File.
   
   
3. In the Database To Save As MDE dialog box, select the database you want to save as an MDE file, and then click Make MDE.
   
   
4. In the Save MDE As dialog box, specify a file name for the database and the location where you want to save it, and then click Save.

   Your original database is unchanged and a new copy is saved as an MDE file using the file name and location you specified in step 4.

Note Saving a database as an MDE file doesn’t create a run-time version of the database. To use an MDE database, users must have Microsoft Access 97 installed. Alternatively, if you have Microsoft Office 97, Developer Edition, you can save a database as an MDE file and then use the Setup Wizard to create a distributable run-time version of it.

Caution Be sure to save a backup copy of your original database in a safe place. If you need to modify the design of forms, reports, or modules in your MDE file, you must open the original non-MDE database, modify the objects, and then save the database again as an MDE file. Also, databases saved as MDE files in Microsoft Access 97 cannot be opened or converted in later versions of Microsoft Access. To convert or open it in later versions of Microsoft Access, you must use the original database.