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Data bases 2, Prof. Comai, Prof. Paraboschi, June 30th, 2011 – Time: 2h 30m A. Active databases (6 points) A company sells furniture, managing warehouses and stores. Every kind of furniture is available in the warehouses in distinct quantities, and the system keeps track of the dista nces between between warehouses and stores. Stores issue orders for the furniture by inserting them into table F URNITURE REQUEST , and transfers from warehouses to stores are descr ibed in table PROGRAMMED DELIVERY . DISTANCE (StoreCode , WHouseCode , Km) WAREHOUSE AVAILABILITY (WHouseCode , FurnitureType , AvailableQty) FURNITURE REQUEST (StoreCode , FurnitureType , RequestedQty) PROGRAMMED DELIVERY (StoreCode , WHouseCode , FurnitureType , DeliveryQty) 1. Design an active rule system that, at each furnitur e request, identifies the warehouses that will be t he source of the delivery, depending on availability and minimizing the distan ce. One or more deliveries can be programmed, until the requested quantity is reached – indeed, it can happen that the nearest st ore is not able to fulfill the request. We can assu me that requests are “produced” by transactions independent from the rules and are “consumed” by the rules, and that deliveries are “p roduced” by rules and “consumed”, at delivery completion, by transactions independent from the rules. Note : it is important to create deliveries that are consistent in number and overall quantity with the furniture request that originated them, even if mor e than one warehouse is involved in the deliveries. Briefly explain how the solution satisfies this requirement. (5 points) 2. Briefly discuss the termination of the designed rule system. (1 point) B. Distributed databases - Fragmentation (4 points) Take into consideration the data…