1. CSE 441: Systems Analysis & Design Basic CASE Models of Visible Analyst Lab2 Yusuf Altunel

2. The Basic CASE Models  Functional Decomposition Model (FDM) - Business Model  Entity Relationship Model (ERM) - Data Model  Object Model (OCM) - Object Class Model  Process Model (DFD) - Data Flow Diagram

3. Structured Modelling Techniques OVERVIEW  Large systems can be partitioned for further analysis  into component subsystems  or sub-functions.  Specifications for individual components  are easier and faster  than to define than the total system.  The interaction between the parts  can be planned, designed and implemented  to reflect improved information flows and controls.  More than one person  can work with the same system in the network edition.

4. ENTITY RELATIONSHIP MODELING Entity Relationship Modeling or Data Modeling The technique used by Visible Analyst for representing data. The purpose of this technique is to graphically demonstrate how entities are related to one another. An entity could be Customer, Product, Inventory, Supplier, Sale, or some other label generally in the form of a singular noun.

5. ERD  ERD (Entity Relationship Diagram)  The diagramming technique used for Data Modelling  Relationships between entities are described in terms of their CARDINALITY - one-to-one - one-to-many - many-to-many

6. Relationship cardinality ratio  Think up an example of a 1:1 relationship?  1:1  Think up an example of a 1:M relationship?  1:M  How about a M:M relationship?  M:M A department has 1 manager A student takes courses Customers buying products

8. DFD (Data Flow Diagram)  The diagramming technique used for PROCESS MODELLING  The DFD consists of data flows, processes, data stores, external entities.  Methodologies used for Process Modeling: -Yourdon/DeMarco -Gane & Sarson -SSADM - Metrica.  Visible Analyst implements these techniques.

9. Example of a DFD

11. End of Lab-2