Hi, I need help bad, im trying to make an E-R diagram from the following:
The City House Service (CHS) is an onoprofit service that advocates the development and inprovement of low-income housing. The CHS operates in a metropolitan area of approx. 2.2 million people in a mid-west city.
The CHS maintains data about the location, availability, and condition of low-income housing in 22 different census tracts in the metro. area. Within the boundaries of these tracts are approx. 250 different buildings that provide low-income housing. On average, each building contains 25 apartments or other units.
The CHS keeps data about each Census tract, including geographical boundaries, median income of population, elected officials, pronciple business, principle investors involved in attributes in that tract, and other dempgraphic and economic data. It also maintains a limited amout of data about crime. For each building, the CHS stores the name, address, size, owner(s) name and address, mortgagor(s) name and address, renovations and repairs, and availability of facilities for handicapped people. In addition, the CHS keeps a list of each of the units within each building, including the type of unit, size, number of bedrooms, number of baths, kitchen and dining facilities, location in the building, and any special remarks. The CHS would like to maintain data regarding the average occupancy rates for each unit, but to date, it has been unable to collect or store such data. The CHS does, however, keep data about whether a given units is occupied.
The CHS serves as an information clearinghous and offers 3 basic services. First, it works with politicians, lobbyists, and advocacy groups to support legislation that encourages the development of low-income housing through tax incentives, developmental zoning perferences, and other legislative inducements. To accomplish this, the CHS provdes inforation about low-income housing to state, county, and city governents. Second, through speeches, seminars, displays at convenctions, and other public relations activites, the CHS officials strive to raise the community's consciousness about the need for low-income housing. Finally, the CHS provides information about the avaiability of low-income housing to other agencies that work with the low-income and homeless population.
You need to do the following work:
1. Developing an E-R diagram for a database to support the the tracking needs of the CHS, including possible weak entities within this data model
2. Specifying tables and their promary keys and foreign keys.
3. Describing how you have represented weak entities in those tables.
The only tables taht i know of are: Building, Mortgagors, Unit(s) Census government and census tract. My teacher said there would be a minmum of 7 tables and i believe owner would be one.
If anyone could give me any guidance on this, it would be greatly apprciated.