When you first begin to build your report, you want to be sure to select the data source that makes the most sense for your report and use that as your Primary Query. For example, if you wanted to create a sales report, you would likely select either the Sales Order, Sales Item, or Item Fulfillment data source. If you simply want an inventory report, you would select the Inventory History data source. If you wanted a buying report, you would likely select either the PO or PO Manifest Item data source.
However, data sources don't exist in bubbles. The data sources are linked to each other, allowing you to access data indirectly. These links are mapped below:
Note that the arrows point towards data sources that can be accessed indirectly. So for example, if you used the Inventory History data source, you could also access data from the Lots Received data source. Furthermore, you could access any data accessible through the Lots Received data source. That would include: PO Received On, Line Received On/PO Item, Receiving Line, and SKU.
However, the link doesn't work the other way around. In the same example, you can't access Inventory History data through the Lots Received source.
Sample: Inventory History data source
To visualize the point clearly, look to the chart below. This shows all the different data sources that you could access by using the Inventory History data source.
Sample: PO Manifest Item data source
Similarly, this chart displays the data sources accessible through the PO Manifest Item data source.