Presentation is loading. Please wait.

Presentation is loading. Please wait.

Modeling and Evaluation. Modeling Information system model –User perspective of data elements and functions –Use case scenarios or diagrams Entity model.

Similar presentations


Presentation on theme: "Modeling and Evaluation. Modeling Information system model –User perspective of data elements and functions –Use case scenarios or diagrams Entity model."— Presentation transcript:

1 Modeling and Evaluation

2 Modeling Information system model –User perspective of data elements and functions –Use case scenarios or diagrams Entity model –ER Diagrams –UML class diagrams Transaction model –Processes and transactions the user sees –Inputs, outputs, and manipulations

3 Additional documentation Data dictionary –Listing of tables, columns, datatypes, constraints, examples –Physical data model (database schema) Other views of system?

4 What is a good model? Simplicity – generally, the simpler, the easier to understand and implement, and the more flexible Flexibility – how easily can the data model adapt to changing requirements? Integration – how consistent is the data with the rest of the organization’s data? – Better integration means more reuse, modifications are simpler, model provides easier understanding of business applications. Understandability Implementability

5 Database standards Naming data items Naming database objects Locations for objects Sample standards

6 ER modeling exercise Develop ER diagram

7 Evaluation Existing systems Meeting with users Merging views

8 View Integration Exercise Gather perspectives from users (assume none are complete) Lots of decisions when integrating –Integration strategy – one after another or all at once? –Resolving conflicts Dependency Key behavioral –Conformation of schemas – often requires more info than originally gathered


Download ppt "Modeling and Evaluation. Modeling Information system model –User perspective of data elements and functions –Use case scenarios or diagrams Entity model."

Similar presentations


Ads by Google