A-level Computing/AQA/Problem Solving, Programming, Operating Systems, Databases and Networking/Databases
Produce a data model from the given data requirements for a simple scenario involving two or three entities.
Be able to normalise relations to Third Normal Form.
Explain the concept of a relational database.
Define the terms:
Learn about Structured Query Language (SQL)
Use SQL to retrieve, update, insert and delete data from several tables of a relational database (see Teacher Resource Bank)
Data Definition Language (DDL)
Explain the term DDL. Use DDL to define a database (see Teacher Resource Bank for commands/statements).
Conceptual Data Model
Entity Relationship Diagrams
An entity relationship diagram is used at the Analysis stage to help the analyst to model and represent the entities involved in the problem domain. These models can then be developed into designs for tables and relationships in a proposed database system.
Tuple sometimes called a record, a set of attribute values, (a row of a table)
Attribute a named column in a table
Primary Key a attribute that uniquely identifies a tuple
Relation a table
Relational Database a collection of tables
Composite Key where a collection of attributes uniquely identify a tuple rather than just one
Foreign Key An attribute in one table that is a Primary key in another table, often there to reference to said table later