Why Do My Database Changes Disappear After Closing My SQL Server Compact Edition Application?

Troubleshooting Database Changes Lost on Application Closure

During debugging with SQL Server Compact Edition 4 and VS2012 Express, database modifications made via a console application might seem to vanish after closing the application. This often stems from using the |DataDirectory| placeholder in your connection string.

Understanding the |DataDirectory| Problem

|DataDirectory| points to a temporary location within your project's bin folder. The database used during debugging resides here and is deleted upon session termination. This explains why changes are visible in the debugger but disappear afterward. The Visual Studio Server Explorer, however, might show a seemingly unchanged database in your project's main folder.

Resolving the Issue

Here are several approaches to fix this:

• Modify Database File Properties: In Visual Studio's Solution Explorer, alter the "Copy to Output Directory" property of your database file. Set it to "Copy if Newer" or "Do not copy". This prevents the database from being automatically copied to the bin folder.
• Dual Database Connections: Create two connections in the Server Explorer: one targeting the database in your project folder (for debugging) and another pointing to the database in the bin folder (to monitor changes).
• MS Access Database Considerations: Note that with MS Access databases, simply viewing the table in the Server Explorer can change the database's timestamp. If "Copy if Newer" is selected, the database file will be unnecessarily copied to the output directory. Using "Do not copy" is recommended in this scenario.

The above is the detailed content of Why Do My Database Changes Disappear After Closing My SQL Server Compact Edition Application?. For more information, please follow other related articles on the PHP Chinese website!