The Auto-Layout function automatically rearranges symbols in the active diagram. The symbols are arranged in rows from left to right horizontally. This function is useful when you want to line up multiple tables in the diagram automatically.
To call this function click Auto-Layout button on Diagram tab of the Ribbon. Please note, that auto-layout operation is undoable in most cases.
See also:
Diagram: Using Snapping Grid | Zooming a Diagram