I have not had much use for UDL (Universal Data Link) files in the past, but recently I found out just how useful they can be. Today I encountered an issue with Crystal Reports 9 calling SQL Server with a blank password when the connection was set within Crystal Reports. After much research and testing I found that the only way to correct this was to force Crystal Reports to use a UDL file to obtain its connection information.
For anyone not sure exactly what a UDL file is, it is basically a file that one can create and use to centralize database connection information. So it functions along the lines of an ODBC data source, or a little like an old .ini file… or for the web, like a web.config file. The only difference being that like an ODBC datasource, Windows will present a forms like view of the connection information in the UDL file when it is opened.
Please see my post on how to create and configure UDL files for details of how to manage them.
In general, creating and managing a UDL file is quite similar to setting up a standard System ODBC connection, except that the UDL file can be copied and pasted like a standard text file. Further, the UDL file allows you to select from a number of OLE DB data providers in order to connect to a variety of potential data sources.
This modularity is nice since you can ZIP the UDL file up along with the program that needs to reference it, and of course centralizing the connection management is very useful when maintaining a large number of reports.
7 thoughts on “UDL Files: Centralizing your DataSource Connections – Overview”
It is great that there are other ways to define one’s connection to a database other than the standard system ODBC. It can be tough fiddling with the different drivers and their versions.
So true, I’m glad this alternative exists. In the case of the mysterious two-step login attempts of Crystal Reports using a blank password this connection type option really saved the day. With any luck our boss will agree to move the most popular Crystal Reports to using a UDL file to manage the connection.
Hey, can I use your post on my website with a linkback?
Sure, sounds good. Glad you found the post interesting.