<![CDATA[What is the connection string for connecting to local db file (.mdf)]]>I use the following connection string to connect to database in the sqlserver instance SQLEXPRESS:

QString connStr = "DRIVER={SQL SERVER};SERVER=.\\SQLEXPRESS;DATABASE=dbName;";

But I want now to connect to SQL Server database file (.mdf) and I already installed Microsoft SQL Server 2016 LocalDB. What connection string should I use?

I tried the following connection string:

QString connStr = "DRIVER={SQL SERVER};SERVER=%1;AttachDbFileName=%2;"
db.setDatabaseName(connStr.arg("(LocalDB)\\v11.0",dbFilename));

And I also tried a different server:

db.setDatabaseName(connStr.arg("(LocalDB)\\MSSQLLocalDB",dbFilename));

But none of them works and throw the same error:

"[Microsoft][ODBC SQL Server Driver][DBNETLIB]SQL Server does not exist or access denied. [Microsoft][ODBC SQL Server Driver][DBNETLIB]ConnectionOpen (Connect()). QODBC3: Unable to connect"
]]>https://forum.qt.io/topic/90641/what-is-the-connection-string-for-connecting-to-local-db-file-mdfRSS for NodeMon, 15 Jun 2026 11:23:25 GMTSat, 12 May 2018 06:27:43 GMT60<![CDATA[Reply to What is the connection string for connecting to local db file (.mdf) on Fri, 01 Jun 2018 16:00:10 GMT]]>@mrjj said in What is the connection string for connecting to local db file (.mdf):

Hi
Im not sure ODBC likes LocalDB

https://social.msdn.microsoft.com/Forums/sqlserver/en-US/f21d9354-01f1-484d-b5f8-ea63e0ca76e5/odbc-driver-13-for-sql-server-localdb-problem?forum=SQLServer2016Preview

I wonder if that have been fixed with newer versions ?

Thanks @mrjj for your help, I followed the link you provide and finally found a solution to my problem, I put the solution here.

]]>https://forum.qt.io/post/461434https://forum.qt.io/post/461434Fri, 01 Jun 2018 16:00:10 GMT<![CDATA[Reply to What is the connection string for connecting to local db file (.mdf) on Sat, 12 May 2018 09:30:43 GMT]]>Hi
Im not sure ODBC likes LocalDB

https://social.msdn.microsoft.com/Forums/sqlserver/en-US/f21d9354-01f1-484d-b5f8-ea63e0ca76e5/odbc-driver-13-for-sql-server-localdb-problem?forum=SQLServer2016Preview

I wonder if that have been fixed with newer versions ?

]]>https://forum.qt.io/post/457807https://forum.qt.io/post/457807Sat, 12 May 2018 09:30:43 GMT