Last week at the annual Tableau user conference, Tableau and Teradata both announced that Tableau now supports Teradata OLAP as a first class data source.  You can watch a good video of how all this works:  This is a great development because now you can do all your OLAP aggregations in Teradata and easily do all the analysis and visualization in Tableau.  In the past, you needed to pull all the data from Teradata into Tableau and manipulate all the data from there.  The new solution is much more scalable and performant.