Data Source Name (DSN)

Definition of Data Source Nama in the Network Encyclopedia.

What is Data Source name (DSN)?

DSN stands for Data Source Name, is a unique name used to create a data connection to a database using open database connectivity (ODBC). The data source name (DSN) is used by applications that need to access or manage data in the database.

All ODBC connections require that a DSN be configured to support the connection. When a client application wants to access an ODBC-compliant database, it references the database using the DSN.

Data Source name (DSN)
Data Source Name (DSN)

You can configure a DSN for an ODBC-compliant database using the Microsoft Windows NT ODBC or the Windows 2000 Administrative Tools\Data Sources (ODBC) utility in Control Panel. You can create three kinds of DSNs:

  • A user DSN, which is visible only to the user who creates it and can be used only on the current machine.
  • A system DSN, which is visible to all users on the machine and is also accessible to Windows NT and Windows 2000 services. A system DSN is stored in the registry.
  • A file DSN, which can be shared by users who have the same ODBC drivers installed. A file DSN is stored in a file.

Examples of Data Source Name usage

ASP (VBScript) code to open a DSN connection might look like the following:

Dim DatabaseObject1
Set DatabaseObject1 = Server.CreateObject("ADODB.Connection")

In PHP using the PEAR::DB package to open a connection without an external DSN (a “DSN-less connection”, i.e., using a Connection String), the code might resemble the following

//$dsn = "<driver>://<username>:<password>@<host>:<port>/<database>";
$dsn = "mysql://john:pass@localhost:3306/my_db";
$db = DB::connect($dsn);


When you design Web applications that use Microsoft ActiveX Data Objects (ADO) for accessing database information, be sure to use either a file DSN or a system DSN because ADO does not work with user DSNs.


Articles posted after being checked by editors.

Recent Content

link to Named Pipe

Named Pipe

Named Pipe is an interprocess communication mechanism that provides reliable, connection-oriented, two-way communication between processes on two computers. Named pipes are one form of client/server...