Version independent local DB in Visual Studio 2015

There’s some new naming conventions coming for MSSQL LocalDB when Visual Studio 2015 ships. I found these while working on the Humanitarian Toolbox Crisis Checkin project. As more developers start using machines with VS 2015, especially machines that didn’t have a previous version installed, you may run into the same problem.

The web.config for Crisis Checkin on a developer box contains this connection string (highlight added):


<add name="CrisisCheckin" connectionString="Data Source=(localdb)\v11.0;AttachDbFilename=|DataDirectory|\crisischeckin.mdf;Integrated Security=True; MultipleActiveResultSets=True;" providerName="System.Data.SqlClient" />


When I ran this on my new Surface Pro III, using VS 2015 Preview, the application would not load. The app could not create and load the database.  After some investigation, creating apps using the new templates, and comparing, I found that I needed to change the connection string as follows:

<add name="CrisisCheckin" connectionString="Data Source=(localdb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\crisischeckin.mdf;Integrated Security=True; MultipleActiveResultSets=True;" providerName="System.Data.SqlClient" />

I asked around, and with the help of a couple team members, I now understand and know what to do.

Starting with this VS2015, the team is moving away from version dependent connection strings. That means, once you adopt VS 2015, you have the option of using a version independent  connection string moving forward. That’s the first recommendation:

To fix this issue for now, and future versions of Visual Studio, replace the version dependent connection string (e.g. “v11.0”) with “MSSQLLocalDB”.

However, you may need to continue to work with team members that are still using VS 2013. If that’s the case, you can follow the second recommendation:

Install the Version 11 LocalDB, which is free. You can then use Visual Studio 2015 (preview), but your database engine will be MSSQL LocalDB version 11.0.

Personally, I’d gravitate toward using the version independent connection strings as soon as possible. We will do that on crisis checkin once VS 2015 is officially released.

I hope this saves you some research when you first encounter this change.

Created: 2/5/2015 3:01:05 PM

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