Codd’s 12 Rules
Explore Edgar F. Codd's 12 essential rules that define a genuine relational database management system. Understand their historical context and how these principles ensure data consistency, integrity, and accessibility in modern databases. This lesson equips you with a solid basis for recognizing and applying relational database concepts.
We'll cover the following...
We'll cover the following...
- The story behind the rules
- Codd’s 12 rules explained
- Rule 0: The foundation rule
- Rule 1: The information rule
- Rule 2: The guaranteed access rule
- Rule 3: Systematic treatment of NULL values
- Rule 4: Dynamic online catalog based on the relational model
- Rule 5: The comprehensive data sub-language rule
- Rule 6: The view updating rule
- Rule 7: High-level insert, update, and delete
- Rule 8: Physical data independence
- Rule 9: Logical data independence
- Rule 10: The integrity independence rule
- Rule 11: The distribution independence rule
- Rule 12: The nonsubversion rule
- Quiz
Let’s dive into the foundational principles that define what a truly relational database is. In the early days of databases, many products claimed to be relational, but not all adhered to the same core principles. To clear up the confusion and establish a standard, the brilliant ...