How do I connect to an Oracle DB or an Inormix DB through Database Explorer/Server Explorer in visual studio 2010?

I am new so please go easy!

I am using visual studio 2010 express. I use the wizard to add a dataset and my only options are:

• Microsoft Access DB file
• Microsoft SQL server compact
• Microsoft SQL server db file

I have a few different types of databases set up on my system that I typically query from:

• informix odbc
• oracle
• postgre

I am at a loss as to how to get vi开发者_StackOverflow中文版sual studio to recognize these data source types... any help is greatly appreciated