Connecting to SQL Server using Oracle SQL Developer
I followed these instructions to add the jTDS Java library to Oracle SQL Developer. Basically it's about downloading the jTDS zip, unzipping it in some place you can reach later and then add the jTDS.jar as a JDBC third party driver in SQL Developer ((In the main menu) Tools > Preferences > (On the tree menu in the new window) Database > Third party JDBC drivers > Click on 'Add entry')

I was then able to use my credentials to connect to a SQL Server instance/database using the following connection details. I'm currently using Oracle Developer 4.0.1.14.



The default port for SQL Server instance is 1433, however your SQL Server instance may be running on a non default port. The following site has different methods to determine the port.

http://www.mssqltips.com/sqlservertip/2495/identify-sql-server-tcp-ip-port-being-used/