Database 1
Database Design
- Prof. dr. Paul M.E. De Bra
- Dept. of Computer Science
- Eindhoven Univ. of Technology
Augmentation and Transitivity rules
- Prove (using the definition of fd) that if X, Y and Z are sets of attributes of a relation scheme R, and the fd X Y holds in R, then XZ YZ also holds in R.
- Prove (using the definition of fd) that if X, Y and Z are sets of attributes of a relation scheme R, and the fds X Y and Y Z hold in R, then X Z also holds in R.
Bogus rules
- Disprove that if X and Y and Z are sets of attributes of a relation scheme R, and the fd X Y holds in R, then Y X also holds in R.
- Disprove that if X, Y and Z are sets of attributes of a relation scheme R, and the fds X Y and Y Z hold in R, then Z X also holds in R.
- Disprove that if X, Y and Z are sets of attributes of a relation scheme R, and the fds XY Z holds in R, then X YZ also holds in R.
Preparation for colstruction 2
- The preparation is for colstruction 2 instead of labsession 2 because of a holiday.
- Study chapter 7 of the database book, up to and including section 7.3.3.
- 7.3.2 explains inference rules, and the closure of a set of functional dependencies
- 7.3.3 explains the closure of attribute sets