Connection strings for SQL Server 2008

.NET libraries for SQL Server 2008

• .NET Framework Data Provider for SQL Server - SqlConnection
• .NET Framework Data Provider for OLE DB - OleDbConnection
• .NET Framework Data Provider for ODBC - OdbcConnection
• Context Connection

OLE DB providers for SQL Server 2008

• SQL Server Native Client 10.0 OLE DB Provider
• SQLXML 4.0 OLEDB Provider

ODBC drivers for SQL Server 2008

• SQL Server Native Client 10.0 ODBC Driver

Developers Community

Find solutions and post questions regarding connection string related issues.
Forum for SQL Server 2008

.NET Framework Data Provider for SQL Server

Type .NET Framework Class Library Usage System.Data.SqlClient.SqlConnection Manufacturer Microsoft

More info and class library downloads

Set example values

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;

 

 

Trusted Connection from a CE device

A Windows CE device is most often not authenticated and logged in to a domain but it is possible to use SSPI or trusted connection and authentication from a CE device using this connection string.

    

Data Source=myServerAddress;Initial Catalog=myDataBase;Integrated Security=SSPI;
User ID=myDomain\myUsername;Password=myPassword;

Note that this will only work on a CE device.
 

 

Connect via an IP address

    

Data Source=190.190.200.100,1433;Network Library=DBMSSOCN;Initial Catalog=myDataBase;
User ID=myUsername;Password=myPassword;

DBMSSOCN=TCP/IP is how to use TCP/IP instead of Named Pipes. At the end of the Data Source is the port to use. 1433 is the default port for SQL Server. Read more here.
 

 

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;

Why is the Database parameter needed? If the named database have already been attached, SQL Server does not reattach it. It uses the attached database as the default for the connection.
 

 

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;

Why is the Database parameter needed? If the named database have already been attached, SQL Server does not reattach it. It uses the attached database as the default for the connection.
 

 

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;

To use the User Instance functionality you need to enable it on the SQL Server. This is done by executing the following command: sp_configure 'user instances enabled', '1'. To disable the functionality execute sp_configure 'user instances enabled', '0'.
 

 

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;

There is ofcourse many other ways to write the connection string using database mirroring, this is just one example pointing out the failover functionality. You can combine this with the other connection strings options available.
 

 

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;

See also the List of all SqlConnection connection string properties
 

 

SQL Server Native Client 10.0 OLE DB Provider

Type OLE DB Provider Usage Provider=SQLNCLI10 Manufacturer Microsoft

More info and provider downloads

Set example values

Standard security

    

Provider=SQLNCLI10;Server=myServerAddress;Database=myDataBase;Uid=myUsername;
Pwd=myPassword;

Are you using SQL Server 2008 Express? Don't miss the server name syntax Servername\SQLEXPRESS where you substitute Servername with the name of the computer where the SQL Server 2008 Express installation resides.
When to use SQL Native Client?
 

 

Trusted connection

    

Provider=SQLNCLI10;Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;

Equivalent key-value pair: "Integrated Security=SSPI" equals "Trusted_Connection=yes"
 

 

Connecting to an SQL Server instance

The syntax of specifying the server instance in the value of the server key is the same for all connection strings for SQL Server.

    

Provider=SQLNCLI10;Server=myServerName\theInstanceName;Database=myDataBase;
Trusted_Connection=yes;

 

 

Prompt for username and password

This one is a bit tricky. First you need to set the connection object's Prompt property to adPromptAlways. Then use the connection string to connect to the database.

    

oConn.Properties("Prompt") = adPromptAlways

oConn.Open "Provider=SQLNCLI10;
Server=myServerAddress;DataBase=myDataBase;

 

 

Enable MARS

    

Provider=SQLNCLI10;Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;
MARS Connection=True;

 

 

Encrypt data sent over network

    

Provider=SQLNCLI10;Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;
Encrypt=yes;

 

 

Attach a database file on connect to a local SQL Server Express instance

    

Provider=SQLNCLI10;Server=.\SQLExpress;AttachDbFilename=c:\asd\qwe\mydbfile.mdf;
Database=dbname;Trusted_Connection=Yes;

Why is the Database parameter needed? If the named database have already been attached, SQL Server does not reattach it. It uses the attached database as the default for the connection.
 

 

Attach a database file, located in the data directory, on connect to a local SQL Server Express instance

    

Provider=SQLNCLI10;Server=.\SQLExpress;AttachDbFilename=|DataDirectory|mydbfile.mdf;
Database=dbname;Trusted_Connection=Yes;

Why is the Database parameter needed? If the named database have already been attached, SQL Server does not reattach it. It uses the attached database as the default for the connection.
 

 

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.

    

Provider=SQLNCLI10;Data Source=myServerAddress;Failover Partner=myMirrorServerAddress;
Initial Catalog=myDataBase;Integrated Security=True;

There is ofcourse many other ways to write the connection string using database mirroring, this is just one example pointing out the failover functionality. You can combine this with the other connection strings options available.
 

 

.NET Framework Data Provider for OLE DB

Type .NET Framework Wrapper Class Library Usage System.Data.OleDb.OleDbConnection Manufacturer Microsoft

More info and wrapper class library downloads

Set example values

Use an OLE DB provider from .NET

    

Provider=any oledb provider's name;OledbKey1=someValue;OledbKey2=someValue;

See the respective OLEDB provider's connection strings options. The .net OleDbConnection will just pass on the connection string to the specified OLEDB provider. Read more here.
 

 

SQL Server Native Client 10.0 ODBC Driver

Type ODBC Driver Usage Driver={SQL Server Native Client 10.0} Manufacturer Microsoft

More info and driver downloads

Set example values

Standard security

    

Driver={SQL Server Native Client 10.0};Server=myServerAddress;Database=myDataBase;
Uid=myUsername;Pwd=myPassword;

Are you using SQL Server 2008 Express? Don't miss the server name syntax Servername\SQLEXPRESS where you substitute Servername with the name of the computer where the SQL Server 2008 Express installation resides.
When to use SQL Native Client?
 

 

Trusted Connection

    

Driver={SQL Server Native Client 10.0};Server=myServerAddress;Database=myDataBase;
Trusted_Connection=yes;

Equivalent key-value pair: "Integrated Security=SSPI" equals "Trusted_Connection=yes"
 

 

Connecting to an SQL Server instance

The syntax of specifying the server instance in the value of the server key is the same for all connection strings for SQL Server.

    

Driver={SQL Server Native Client 10.0};Server=myServerName\theInstanceName;
Database=myDataBase;Trusted_Connection=yes;

 

 

Prompt for username and password

This one is a bit tricky. First you need to set the connection object's Prompt property to adPromptAlways. Then use the connection string to connect to the database.

    

oConn.Properties("Prompt") = adPromptAlways


Driver={SQL Server Native Client 10.0};Server=myServerAddress;Database=myDataBase;

 

 

Enable MARS

    

Driver={SQL Server Native Client 10.0};Server=myServerAddress;Database=myDataBase;
Trusted_Connection=yes;MARS_Connection=yes;

 

 

Encrypt data sent over network

    

Driver={SQL Server Native Client 10.0};Server=myServerAddress;Database=myDataBase;
Trusted_Connection=yes;Encrypt=yes;

 

 

Attach a database file on connect to a local SQL Server Express instance

    

Driver={SQL Server Native Client 10.0};Server=.\SQLExpress;
AttachDbFilename=c:\asd\qwe\mydbfile.mdf;Database=dbname;Trusted_Connection=Yes;

Why is the Database parameter needed? If the named database have already been attached, SQL Server does not reattach it. It uses the attached database as the default for the connection.
 

 

Attach a database file, located in the data directory, on connect to a local SQL Server Express instance

    

Driver={SQL Server Native Client 10.0};Server=.\SQLExpress;
AttachDbFilename=|DataDirectory|mydbfile.mdf;Database=dbname;Trusted_Connection=Yes;

Why is the Database parameter needed? If the named database have already been attached, SQL Server does not reattach it. It uses the attached database as the default for the connection.
 

 

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.

    

Driver={SQL Server Native Client 10.0};Server=myServerAddress;
Failover_Partner=myMirrorServerAddress;Database=myDataBase;Trusted_Connection=yes;

There is ofcourse many other ways to write the connection string using database mirroring, this is just one example pointing out the failover functionality. You can combine this with the other connection strings options available.
Please note if you are using TCP/IP (using the network library parameter) and database mirroring, including port number in the address (formed as servername,portnumber) for booth the main server and the failover partner can solve some reported issues.
 

 

.NET Framework Data Provider for ODBC

Type .NET Framework Wrapper Class Library Usage System.Data.Odbc.OdbcConnection Manufacturer Microsoft

More info and wrapper class library downloads

Set example values

Use an ODBC driver from .NET

    

Driver={any odbc driver's name};OdbcKey1=someValue;OdbcKey2=someValue;

See the respective ODBC driver's connection strings options. The .net OdbcConnection will just pass on the connection string to the specified ODBC driver. Read more here.
 

 

SQLXML 4.0 OLEDB Provider

Type OLE DB Provider Usage Provider=SQLXMLOLEDB.4.0;Data Provider=providername Manufacturer Microsoft

More info and provider downloads

Set example values

Using SQL Server Native Client provider

    

Provider=SQLXMLOLEDB.4.0;Data Provider=SQLNCLI10;Data Source=myServerAddress;
Initial Catalog=myDataBase;User Id=myUsername;Password=myPassword;

 

 

Context Connection

Type .NET Framework Class Library Usage
Manufacturer Microsoft

More info and class library downloads

Set example values

Context Connection

Connecting to "self" from within your CLR stored prodedure/function. The context connection lets you execute Transact-SQL statements in the same context (connection) that your code was invoked in the first place.

    

C#
 using(SqlConnection connection = new SqlConnection("context connection=true"))
 {
     connection.Open();
     // Use the connection
 }

VB.Net
 Using connection as new SqlConnection("context connection=true")
     connection.Open()
     ' Use the connection
 End Using

 

 

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Public Function GetAuthorsLastNames() As List(Of String)
        Dim conn As SqlConnection
        Dim cmd As SqlCommand
        Dim result As New List(Of String)
        Dim cmdString As String = "Select au_lname from authors"
        'update this to match the location of pubs on your computer
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                                 "Integrated Security=True;")
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        myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection)
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Server=myServerAddress;Database=myDataBase;Trusted_Connection=yes;