Chap03.pdf - CSC 4710 CSC 6710 Database Systems When needed we will use them*Material based on Fundaments of DATABASE SYSTEMS 7th Edition(Elmasri

Chap03.pdf - CSC 4710 CSC 6710 Database Systems When needed...

This preview shows page 1 - 9 out of 71 pages.

CSC 4710 / CSC 6710 Database Systems Rao Casturi *Material based on Fundaments of DATABASE SYSTEMS 7 th . Edition (Elmasri & Navathe) ** Additional comments, slides are added by Rao Casturi When needed we will use them Rao Casturi - GSU - Database Systems
Data Modeling Using the Entity-Relationship (ER) Model Rao Casturi - GSU - Database Systems Overview of Database Design Process Example Database Application (COMPANY) ER Model Concepts Entities and Attributes Entity Types, Value Sets, and Key Attributes Relationships and Relationship Types Weak Entity Types Roles and Attributes in Relationship Types ER Diagrams - Notation ER Diagram for COMPANY Schema Alternative Notations – UML class diagrams, others Relationships of Higher Degree
Overview of Database Design Process Two main activities: Database design Applications design Focus in this chapter on conceptual database design To design the conceptual schema for a database application Applications design focuses on the programs and interfaces that access the database Generally considered part of software engineering Rao Casturi - GSU - Database Systems
Overview of Database Design Process Rao Casturi - GSU - Database Systems Database Architecture Software Engineering DBMS – Independent DBMS – Coupled
Methodologies for Conceptual Design Entity Relationship (ER) Diagrams Enhanced Entity Relationship (EER) Diagrams Use of Design Tools in industry for designing and documenting large scale designs The UML (Unified Modeling Language) Class Diagrams are popular in industry to document conceptual database designs Rao Casturi - GSU - Database Systems
Example COMPANY DatabaseCreate a database schema designbased on the following (simplified) requirementsof the COMPANY Database:The company is organized into DEPARTMENTs. Each department has a unique name and unique number and an employee who managesthe department. We keep track of the start date of the department manager. A department may have several locations.Each department controlsa number of PROJECTs. Each project has a unique name, unique number and is located at a single location. Rao Casturi - GSU - Database Systems
Example COMPANY Database (Continued) The database will store each EMPLOYEE’s social security number, address, salary, sex, and birthdate. Each employee works for one department but may work on several projects. The DB will keep track of the number of hours per week that an employee currently works on each project. It is required to keep track of the direct supervisor of each employee. Each employee may have a number of DEPENDENTs. For each dependent, the DB keeps a record of name, sex, birthdate, and relationship to the employee. Rao Casturi - GSU - Database Systems
Steps in Building the Conceptual Design PART 1 : Identify Entity Types, Entities, Attributes for the entities Refine the Entities PART 2: Define the relationship between Entity Types Test the relationships with the problem Confirm it with Client Rao Casturi - GSU - Database Systems

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture