When you move the mouse cursor over a node in a diagram, the Canvas displays a limited amount of information about that node. For example, when you move the mouse cursor over a table node, the Canvas displays information like this:
To see detailed information about a node, select the node and view the Description of Selected Node pane.
If a diagram contains more than one query block, a tab for each query block is displayed at the bottom of the Canvas. You can click one of these tabs to see only the corresponding query block. To see the entire diagram again, click the Query tab.