How do I create a beast mode statement to change the name of a column header? For example: Column Heading = X and I want it to be changed to Y.
You cannot change column names in a beast mode. Column names would need to be changed in a dataflow.
If all you need to change is the column name, then you might consider simply changing it in the visualization. In card analyzer (edit mode) you can click on the field names listed across the top of you visualization. When you click them, a drop-down menu will appear and you can enter whatever name you'd like in the "Label" box. A similar approach works for quick filters. Simply click on the field name in the quick filter portion of card analyzer and type in whatever name you'd like.
If you need to actually change the name of the column as it exists in a dataset, then you'll want to use a dataflow. Even then, you can't change the column name; instead, you input the table with the column name you don't like and then output a different table after renaming the column. In a Magic ETL dataflow, you can use a "Select Columns" tile for this purpose.
Thank you very much for the thorough reply! This helps immensely.