Has SAP been implemented at a shipping company? Absolutely and there are many examples. I suggest a review of sap.com. Register your e-mail on the site if you wish to do so. There is no cost and it helps in your search. So search on sap.com for functionality on shipping. Some of the more interesting topics revolve around the special needs of companies to certify their products with governmental customs and duties regulations around the world and scheduling software.
What is the best database software? Opinions differ but I am absolutely against any future use of Oracle. Oracle database pricing imposes a penalty on the SAP Customer. If selection of Oracle increases your Total Cost of Ownership from the start, there are too many alternatives to make it a viable choice. What are the alternatives? MS SQL is a great product. Some folks have a low opinion of its scalability and availability. Perception is a difficult obstacle to overcome. If that is true at your company, look at Max DB from SAP and IBM UDB as viable alternatives.
This is a perspective based upon my work with SAP Solutions Management. I hope this helps