Microsoft SqlClient Data Provider for SQL Server
Standard Security
Server=myServerAddress;Database=myDataBase;User Id=myUsername;Password=myPassword;
Trusted Connection
Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;
Connection to a SQL Server instance
The server/instance name syntax used in the server option is the same for all SQL Server connection strings.
Server=myServerName\myInstanceName;Database=myDataBase;User Id=myUsername;Password=myPassword;
Using a non-standard port
If your SQL Server listens on a non-default port you can specify that using the servername,xxxx syntax (note the comma, it's not a colon).
Server=myServerName,myPortNumber;Database=myDataBase;User Id=myUsername;Password=myPassword;
Connect via an IP address
Data Source=190.190.200.100,1433;Network Library=DBMSSOCN;Initial Catalog=myDataBase;User ID=myUsername;Password=myPassword;
Enable MARS
Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;MultipleActiveResultSets=true;
Attach a database file on connect to a local SQL Server Express instance
Server=.\SQLExpress;AttachDbFilename=C:\MyFolder\MyDataFile.mdf;Database=dbname;Trusted_Connection=Yes;
Attach a database file, located in the data directory, on connect to a local SQL Server Express instance
Server=.\SQLExpress;AttachDbFilename=|DataDirectory|mydbfile.mdf;Database=dbname;Trusted_Connection=Yes;
User Instance on local SQL Server Express
The User Instance feature is deprecated with SQL Server 2012, use the SQL Server Express LocalDB feature instead.
LocalDB automatic instance
Server=(localdb)\v11.0;Integrated Security=true;
LocalDB automatic instance with specific data file
Server=(localdb)\v11.0;Integrated Security=true;AttachDbFileName=C:\MyFolder\MyData.mdf;
LocalDB named instance
To create a named instance, use the SqlLocalDB.exe program. Example SqlLocalDB.exe create MyInstance and SqlLocalDB.exe start MyInstance
Server=(localdb)\MyInstance;Integrated Security=true;
LocalDB named instance via the named pipes pipe name
The Server=(localdb) syntax is not supported by .NET framework versions before 4.0.2. However the named pipes connection will work to connect pre 4.0.2 applications to LocalDB instances.
Server=np:\\.\pipe\LOCALDB#F365A78E\tsql\query;
LocalDB shared instance
Both automatic and named instances of LocalDB can be shared.
Server=(localdb)\.\MyInstanceShare;Integrated Security=true;
Database mirroring
If you connect with ADO.NET or the SQL Native Client to a database that is being mirrored, your application can take advantage of the drivers ability to automatically redirect connections when a database mirroring failover occurs. You must specify the initial principal server and database in the connection string and the failover partner server.
Data Source=myServerAddress;Failover Partner=myMirrorServerAddress;Initial Catalog=myDataBase;Integrated Security=True;
Asynchronous processing
A connection to SQL Server that allows for the issuing of async requests through ADO.NET objects.
Server=myServerAddress;Database=myDataBase;Integrated Security=True;Asynchronous Processing=True;
Using an User Instance on a local SQL Server Express instance
The User Instance functionality creates a new SQL Server instance on the fly during connect. This works only on a local SQL Server instance and only when connecting using windows authentication over local named pipes. The purpose is to be able to create a full rights SQL Server instance to a user with limited administrative rights on the computer.
Data Source=.\SQLExpress;Integrated Security=true;AttachDbFilename=C:\MyFolder\MyDataFile.mdf;User Instance=true;
Specifying packet size
Server=myServerAddress;Database=myDataBase;User ID=myUsername;Password=myPassword;Trusted_Connection=False;Packet Size=4096;