Version

All

Date

2 Feb 2000

Summary

This KBI explains the differences between System, User, and File DSNs.

Technical Background

N/A

Resolution

File DSN

File DSNs keep their connection information in a file and the file can be stored anywhere — a File DSN can be stored on a server for access across the network.

For example, the Visual InterDev 6.0 data connection feature automatically reads the File DSN information and stores it in the data connection.

User DSN

User and System DSNs reside on the machine where they are created.

A User DSN is for one user only and is not shared.

System DSN

System DSNs are stored on the system and controlled by the system, not by the user.

Thus, anyone on the system can reuse any System DSN.

For example, assume there is a development server, a local workstation, and a production server.

Furthermore, the development server and the production server each have a SQL Server database used by a Web application being developed.

An effective way to manage this is to create a System DSN on each system with the same name.

Point the System DSNs on both the development server and the local workstation to the development server’s database.

Point the System DSN on the production server to the production database.

Important: All three DSNs must have the same name.

Argent recommends using System DSNs, never User DSNs.