This illustration shows the order_items
master table and the
inventories
master table. The order_items
table has a primary key that includes
both the
order_id
column and the line_item_id
column. The
inventories
table has a primary
key that includes both the product_id
column and the
warehouse_id
column. The
product_id
column exists in both tables. There is a many to many
relationship
between the order_items
and inventories
tables because
many order items can be available in many inventories.