The best way to view total inventory would be to open the Item table and select “On Hand Quantity” and “Orderable Quantity” from the columns drop down.
On Hand Quantity - Any product on hand, regardless of status or location
Orderable Quantity - Product that can be fulfilled to an Order
To see quantity for an item on any given day in the past, view the Inventory Snapshot table.
To see quantity of SKUs in each location, view the Inventory Detail table.
To see quantity of SKUs on hand AND depleted, view the Perpetual Inventory table.
To audit the movement and usage of SKUs, view the Item Activity table.
Any of the these tables has a long list of columns that can be viewed, sorted, and filtered to accommodate your operation needs.