Hvad er DSN ??

DSN står for Database Source Name og sættes op under dine ODBC indstillinger i Windows kontrolpanelet. ODBC er en forkortelse for Open DataBase Connectivity.


(http://en.wikipedia.org/wiki/Database_Source_Name)


Database Source Names, more commonly seen as the abbreviation, DSN, are data structures used to describe a connection to a database. This DSN will take the form of protocol: subprotocol: host: port: database so as to completely specify all parameters of the connection. The exact format of the DSN will vary depending on your programming language.

Example of use

Using a DSN to connect to a MySQL database through the Web, Web users can submit form entries to a MySQL database by establishing a connection to the MySQL database's DSN.

The advantage of a DSN is that applications can take advantage of any database, as long as DSN is supported (i.e. in Apache/PHP, IIS/ASP)

In ASP (VBScript), to open a DSN connection, the code is:

Dim DatabaseObject1
Set DatabaseObject1 = Server.CreateObject("ADODB.Connection")
DatabaseObject1.Open("DSN=DSNname;")

I PHP kan du fx oprette forbindelse til en database således:

<?php
$dbh = new PDO('mysql:host=localhost;dbname=test', $user, $pass);
?>

Her oprettes en fordindelse til en database, som har DSN'et "mysql:host=localhost;dbname=test" og der logges ind med brugernavnet, som er gemt i variablen $user og passwordet som er gemt i variablen $pass.

(PDO i denne kode står for PHP Data Objects)