IS6145 Database Analysis and Design Lecture 6: Practice with ERDs Rob Gleasure R.Gleasure@ucc.ie www.robgleasure.com

From IS6145 Winter Exam 2016 Draw an Enhanced Fine Granular Design-Specific Entity-Relationship Diagram using Chen’s notation based on the following narrative: A bus company wishes to redesign their data store. At the moment, data are stored for buses according to their registration and the number of seats. Each bus may serve a number of individual routes, each of which is identified by a particular code. Routes will also describe their start and end locations, each individual stop, and the range of individual buses that serve each one. For routes that run during the day, data are also stored regarding their sensitivity to traffic (some will serve routes that slow considerably during rush hour) and whether multiple routes are ever run simultaneously to satisfy demand. For routes that run during the night, data will specify whether they run all week long or only at nights. Night routes may also be allocated a security guard, data for whom includes their name, their gender, and any training courses they may have undertaken. Buses are stored in specific depots, for which the name, address, and contact numbers must be stored. Data are also stored for bus drivers, data for whom will include a name, a date of birth, a job title, and a unique employee ID. These drivers will be allocated a number of specific routes, or alternatively a specific bus.

From IS6145 Winter Exam 2016

From IS6145 Winter Exam 2017 Draw an Enhanced Fine Granular Design-Specific Entity-Relationship Diagram using Chen’s notation based on the following narrative for a hurricane recovery system: For each hurricane, data are recorded for their name, year, and category (which ranges from 1-5). The system also notes whether a hurricane is a follow-on for a previous hurricane. Warnings for specific hurricane are recorded according to their level and date. These warnings may be linked to specific regions, or whom the name and country is noted, as are any particular vulnerabilities. Some regions are urban areas, in which case the city, population, and any relevant rea codes are noted. These urban areas may be served by up to 3 different urban emergency service bodies. These urban emergency service bodies, which may serve up to 5 different urban areas, contain a generic name (e.g. southern emergency service), a contact number, and multiple emergency types. Other regions are rural areas, in which case their population is also noted, as are important infrastructural qualities and a flood-threat level, which may be low, medium, or high. Rural areas may be served by any number of rural emergency service bodies, for whom the service name is noted, as is a contact number, and the umber of individuals working there. Rural areas may also be served by local volunteers, in which case a name, contact number, training details, and any associated machinery is stored. Rural areas must be served at least one of these wo groups, i.e. rural emergency service bodies and volunteers. However, some rural areas are served by both.

From IS6145 Winter Exam 2017