Question

1. The company publishes one regional magazine each in Upper North island (UN), Lower North island (LN), Upper South island (US), and Lower South island (LS). The company has 300,000 customers (subscribers) distributed throughout the four regions. On the first of each month, an annual subscription INVOICE is printed and sent to each customer whose subscription is due for renewal. The INVOICE entity contains a REGION attribute to indicate the customer’s region of residence (UN, LN, US, LS):

CUSTOMER (CUS_NUM, CUS_NAME, CUS_ADDRESS, CUS_CITY, CUS_REGION, CUS_SUBSDATE)

INVOICE (INV_NUM, INV_REGION, CUS_NUM, INV_DATE, INV_TOTAL)

The company is aware of the problems associated with centralized management and has decided that it is time to decentralize the management of the subscriptions in its four regional subsidiaries. Each subscription site will handle its own customer and invoice data. The management at company headquarters, however, will have access to customer and invoice data to generate annual reports and to issue ad hoc queries, such as:

• List all current customers by region.

• List all new customers by region.

• Report all invoices by customer and by region.

Given these requirements, how must you partition the database? How many fragments will you create? Design the database fragments for the INVOICE table and show two rows of sample data for each fragment.

Answer 1

To the east of Australia across the Tasman Sea is the country of New Zealand.New Zealand is one of a number of sets of islands that make up Oceania, also referred to as the Pacific Islands, a region occupying the western and central Pacific Ocean.The Pacific Islands region is generally divided into three subregions: Micronesia, Melanesia, and Polynesia, with New Zealand being part of Polynesia.The Pacific Island region includes more than twenty-five thousand individual small islands representing twenty-five nations and territories.The South and North islands of New Zealand are the second- and third-largest islands, respectively.The North and South Islands of New Zealand are separated by a body of water known as the Cook Straight, which is only about thirteen miles wide at its narrowest point.The North and South Islands together are about the same size as the US state of Colorado.New Zealand also includes a number of smaller nearby islands..............................................................

New Zealand, like Australia, is in the Southern Hemisphere, which means that its seasons are expressed at the opposite times of the seasons in North America.In other words, the warmest summer months are January and February and the cooler winter months are June and July.There are only very moderate seasonal differences, which are slightly more pronounced in the inland areas because the inland areas lack the moderating influence of the ocean.In general, the North Island has somewhat warmer average temperatures than the South Island.In summer, average low temperatures are about 50 °F, with daytime highs around 75 °F.In the winter months, low temperatures average about 35 °F and high temperatures are about 50 °F.The occurrence of more extreme temperatures is limited to the mountainous peaks of the Southern Alps.Snow is common in these mountainous regions but rarely occurs in coastal regions.