Presentation on theme: "Advantages and disadvantages, architectures and data models"— Presentation transcript:
1 Advantages and disadvantages, architectures and data models Lecture 3
2 Advantages redundancies can be reduced inconsistencies can be avoided sometime redundant data is necessaryinconsistencies can be avoideddata can be shareddata independenceimproved maintenance of the IS
3 Advantages integrity can be maintained security can be imposed concurrent access can be achievedbetter recovery mechanismIS’s conflicting requirements can be balanced
4 Disadvantages complexity higher impact of failure seem to require more work (skills, time, resources …)eventually it pays offhigher impact of failurepossibly, reduced local performance
11 Course syllabus - main topics generalitiesthe relational modelSQLdatabase design / modellingdata protectionadvanced topics / new trends
12 ActivityHave you ever used a theoretical model? Have you ever done Maths? Have you ever programmed? How is music described? Can you see any similarities between these disciplines? Can you infer a model for data modelling based on a theoretical model you know and the requirements for data modelling?