ODBC is still a great tool for connect to a database. However, in some environments it's difficult to create a DSN to configure the acess to the database. Or even worse, it's cumbersome to have a configuration file with the DSN name and the DSN itself configured in the ODBC administrator and –maybe– a tnsnames.ora file with more configuration details of the database.

So, a way to override the use of a DSN and configure it directly in our program is convenient. In this page I will explain how to achieve that.

We will start by creating an udl file. For the purpose of this tutorial, I will call mine test.udl. You can create such a file by the means of creating an empty text file (test.txt) and renaming it to test.udl. Open it with double click and you will have something like this: