Learning objectives
Explain the limitations of a file-based approach — duplicated data, inconsistency, dependence between a program and the data it reads, and difficulty in sharing — and describe how a relational database removes each one
Define entity, attribute, record, primary key, composite primary key, candidate key, secondary key and foreign key, and identify each of them in a given set of tables
Draw an entity-relationship diagram for a described scenario, identify one-to-one, one-to-many and many-to-many relationships, and resolve a many-to-many relationship by introducing a linking table
Explain the purpose of normalisation, put a set of data into first, second and third normal form, and state at each step which dependency has been removed
Describe the features of a database management system, including the data dictionary, the developer interface, the query processor and the control of access through views and privileges
Distinguish the logical schema from the physical storage of the data, and explain how data independence allows the storage to be changed without rewriting the applications that use it
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