I have updated the SP for the attached dataset that the tablix is using. The refresh worked fine and I can see my new fields in the shared data set when I look in the Fields tab. My problem is the tablix itself is not giving me access to the new fields. There is a disconnect somewhere and I cannot figure out hot to get the tablix to see the updated fields available in the dataset. I run into this problem frequently and hope I can get a good answer here to return to in the future as I am sure I will need to. I have googled and looked through the suggested questions here and I cannot find one that is directly related to this issue.
I will also know note that the report project is in TFS source control as I read that has some adverse side affects. I have marked the whole project for edit and also went to the folder structure and made sure everything was unset to read only.
I am using SSRS 2008 in VS 2010.
Just found it... I don't understand the need for hidden menus like this..
Click the report itself, then go up to View on the menu and at the very bottom there is "Report Data". From here you can select your dataset and go to its properties and refresh the reports attached dataset's fields. What a pain in the butt.
Here is a link that helps better explain it. http://blog.dontpaniclabs.com/post/2012/01/26/Developings-Reports-for-SQL-Server-Reporting-Services