I'm currently working on a small open source project called Automation.SQL. It is a formalization of my work first explored in this blog post about LocalDb. Justin Rusbatch and we hope to have it out on Nuget shortly (no pressure :P), but first I had to write a few tests around both current versions of LocalDb : v11.0 and v12.0. The first, powered by SQL Server Express 2012, worked like a charm, but the version 12.0 version failed to work on my machine. I did have SQL Express 2014 installed along with LocalDb, but I didn't have an instance. Trying to connect to it via SQL Server management studio (SSMS) ended in failure. Running the following command(s) in a command prompt fixed that.
LocalDB SQL EXPRESS 2014
"C:\Program Files\Microsoft SQL Server\120\Tools\Binn\SqlLocalDB.exe" create "v12.0" 12.0 -s
LocalDB SQL Express 2012
"C:\Program Files\Microsoft SQL Server\110\Tools\Binn\SqlLocalDB.exe" create "v11.0" 11.0 -s
Verify that the command worked by using SSMS to connect to the instance.
Hope this helps others looking to use the newer SQL Express 2014 engine with LocalDB.
Software Developer and All Around Nice Guy
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