Thanks!. Can you please tell how to add multiple tables without joing them in a data source/connection? It keeps asking me to "Please add a join clause" when I was adding second table.
You don't do it from that window/dialog--the options for "Edit Connection" or "Add Table" are used when you want to join data sources together.
If you don't want to join, you just follow the instructions for connecting to data, but do it once for each source. Once you've added your first table, you are done with that connection (don't try to "Add Table"--this option is only for joining data together).
Then, go to "Connect to Data" again to choose a different table/view to connect to as your secondary source.
Simply do the above twice.