SQL
Schema Design: Entities, Attributes and Relationships
How to get from a description of a business to a set of tables: find the entities, give them attributes, connect them, and name everything consistentl...
Database Design
Entities, attributes, relationships, integrity and redundancy.
2 notes
Notes
SQL
Data Integrity, Redundancy and Consistency
The three kinds of integrity a relational database enforces, why redundancy causes anomalies, and where a derived value is worth its maintenance cost.