At the Northeast corner of Alaska's Inner Pasage sits the city of Skagway, an old gold-rush boom-town whose once bustling population has been reduced to a wintertime size of less than 1,000. About the only time Skagway becomes bustling these days is when a big ship works its way up from Seattle or Vancouver during the summer to deposit thousands of tourists in town with lots of money and time to burn. These tourists want to be taken quickly and comfortable to see many of Alaska's famous natural wonders-such as its mountains, glaciers, rivers, islands, and various types of wildlife (bears, seals, whales, elk, etc.). The demand for tourist services in this regard has been growing gradually throughout the last 30 years with no let-up in sight.
To meet this growing demand and also to meet another growing market-the demand for individualized tours to the outer islands and to the Alaskan and Yukon inland territories-a group of native Alaskans of Tlingit people have founded an aircraft expedition company called NAAE (Native Alaskan Aircraft Expeditions). Companies owned and controlled by native people have certain financial and competitive advantages conferred by treaty rights, so the operation of such enterprises has been growing in Alaska. This problem deals with an acquisition cycle of NAAE.
NAAE acquires its aircraft through leases that last 1-3 years. When a lease expires, management decides which of the multiple aircraft on the lease are still desirable and negotiates a new lease for them (usually at much lower per-plane rates of course since the planes are much older). Aircraft are identified by engine #, and they not inserted into the database until they have been leased for the first time. Aircraft not leased for a subsequent period are left in the database anyways. Vendors are not added to the database until a transaction with them occurs. NAAE also tracks individual employee participation in actual transactions. Employee information is put into the database as soon as it is known and before relationships with any other entities are considered.
Cashiers handle cash re disbursements, they are bonded. New cash accounts are added to the database when they are opened. All leases are paid for in full with a check drawn on a single account, but multiple accounts are used in leasing activity. All check numbers are different from each other, even those from different accounts. NAAE pay on the 25th of the month for all leases during the previous month. Cash disbursements take place within other cycles of NAAE.
Required: Using the list of data elements below (don't add or subtract any), construct an REA diagram for NAAE with entities, relationships, and participation cardinalities specified. Additionally, you should use the information in the problem to identify all the tables that should be included in a relational database for NAEE.
DATA ELEMENTS (Don't add or delete any)
-lease contract # -individual plane lease fee -lease date
-aircraft engine # -date aircraft manufactured -check #
-total lease fee -individual accounts payable -check amount
-cash account # -cash account balance -cashier employee #
- lease agent employee # -lease agent name -vendor #
-vendor name -cashier fidelity bond plan -cashier Name
Turn in specifications:
1. One page with a fully drawn (with cardinalities) REA model
2. One page with the tables including primary keys, other attributes, and all necessary foreign keys.