Database Modelling
In this assignment, you are asked to design a database to support the recruitment of casual staff for a school. The major business requirements are summarised below in the Mini Case: Instant Recruitment. You are asked to develop a detailed Entity-Relationship model for this mini case. Your ER model should consist of a detailed ER diagram integrated with itemised discussions on the features of the entities and relationships and all the assumptions you made. The ER diagram and the accompanying document should identify keys, constraints, entity types, relationship types, specialisation/generalisation, etc. The ER diagram should in general have more than 5 entity or relationship types and no more than 15. This means that students will have to selectively identify those most important entity types and relationship types for their work and for the fulfillment of the key business functionalities. More concretely, your deliverables should include
1. Executive Summary on the enterprise need in succinct terms, and on what has actually been done in your assignment and to what extent. It must be concise and right to the point.
2. A list of supplementary business rules or assumptions that underpin your particular database design. When pertinent, link them to the part of your database design with short comments.
6. A list of 5 most important (and mutually dissimilar as much as possible) queries in English (not SQL) the Instant Recruitment as a business will typically make through this database system, and an indication on which of these queries are feasible (i.e. achievable) under your current design.
The ER diagram should include, among others, representative attributes for all entity types, proper subclassing, and correct participation multiplicities for the relationship types. It should be meaningfully and well designed, and should also include all relevant and necessary aspects, and indicate any supplementary business rules if you decide to introduce.
Among all the weak entity types, explain for one of them why it is a weak entity type. If your current design doesn't have any weak entities, then explain which one of your current entities may be made a weak entity and why.
Among all the generalisation/specialisation cases in the ER diagram, find a relatively nontrivial one in terms of the subclassing complexity, and explain the meaning of the actual subclassing in this case and the mearning of the associated participation and disjoint constraints.