'Weak entity type' diaporamas de présentation

1.44k views • 123 slides

Chapter 2

Chapter 2. Entity-Relationship Model. Chapter 11 & 12 in Textbook. Database Design. Steps in building a database for an application: 1. Understand real-world domain being captured. 2. Specify it using a database conceptual model (E/R,OO).

923 views • 75 slides

More on ER Model Detail Relationships

More on ER Model Detail Relationships. 4. Detail Conceptual Data Model. Attributes. Attribute A property or characteristic of an entity type that is of interest to the organisation Simple Attribute An attribute that cannot be broken down into smaller components e.g. Emp No. Emp No.

784 views • 65 slides

Chapter 3: Modeling Data in the Organization

Chapter 3: Modeling Data in the Organization. Business Rules. Statements that define or constrain some aspect of the business Assert business structure Control/influence business behavior Expressed in terms familiar to end users Automated through DBMS software. Scope of Business Rules.

782 views • 55 slides

Chapter 3

Chapter 3. Relational Model. Chapter 4 in Textbook. Database Design. Steps in building a database for an application:. Real-world domain. Conceptual model. DBMS data model. Create Schema (DDL). Load data (DML). Relational Model.

403 views • 40 slides

Relational Database Design by ER- and EER-to-Relational Mapping

Chapter 7. Relational Database Design by ER- and EER-to-Relational Mapping. ER-to-Relational Mapping Algorithm. Step 1: Mapping of Regular Entity Types. For each regular entity type E in the ER schema, create a relation R that includes all the simple attributes of E.

674 views • 39 slides

Conceptual Modeling with ER Diagrams

Conceptual Modeling with ER Diagrams. Peter Chen introduced ER Diagrams. E-R Modeling. E-R Modeling is a design methodology for modeling the Entities Relationships using a diagram with specified shapes for entities, relationships, roles of entities in these relationships, and cardinality.

764 views • 35 slides

Translation of EER model into relational model

567 views • 35 slides

Chapter Outline

Chapter Outline. ER-to-Relational Schema Mapping Algorithm Step 1: Mapping of Regular Entity Types Step 2: Mapping of Weak Entity Types Step 3: Mapping of Binary 1:1 Relation Types Step 4: Mapping of Binary 1:N Relationship Types. Step 5: Mapping of Binary M:N Relationship Types.

502 views • 32 slides

Chapter Outline

Chapter Outline. ER-to-Relational Schema Mapping Algorithm Step 1: Mapping of Regular Entity Types Step 2: Mapping of Weak Entity Types Step 3: Mapping of Binary 1:1 Relation Types Step 4: Mapping of Binary 1:N Relationship Types. Step 5: Mapping of Binary M:N Relationship Types.

416 views • 32 slides

EXAMPLE

EXAMPLE. Subclasses and Superclasses. Entity type may have sub-grouping that need to be represented explicitly. Example: Employee may grouped into secretary, engineer, manager, technician, exempt and non-exempt. Sub-groups are called subclass and employee superclass

461 views • 29 slides

Database Systems

Database Systems. Conceptual to Relational Modeling II Lecture # 11 Feb 25 th 2011. ER Model => Relational Model. Step 1: Regular Entities (and Single-valued attributes). Step 2: Many-to-Many Relationships Step 3: Many-to-One Relationships Step 4: One-to-One Relationships

391 views • 28 slides

Logical Model

383 views • 25 slides

Entity Relational Diagram (ERD) Modeling

Entity Relational Diagram (ERD) Modeling This particular lecture is mainly prepared by the instructors at the University of Manitoba. Some contents are modified by Dr. Hadaegh and Mr. Jones for the students at the Red River College. ERD Model Entity-Relationship, ER Model

443 views • 25 slides

Fundamentals/ICY: Databases 2013/14 Week 6: Monday

Fundamentals/ICY: Databases 2013/14 Week 6: Monday. John Barnden Professor of Artificial Intelligence School of Computer Science University of Birmingham, UK. Module Eval Forms Today Hooray! You have to wait till the end!. Reminder of Friday. Weak Entity Types.

345 views • 24 slides

CONCEPTS OF E-R MODEL

CONCEPTS OF E-R MODEL. CONTENTS Entity Attributes Data Value Entity Types Types of Entity Types Relationships Relationship Constraints. Entity

342 views • 24 slides

A Demo of Logical Database Design

A Demo of Logical Database Design. Aim of the demo. To develop an understanding of the logical view of data and the importance of the relational model To consider entities, attributes, and tables within the relational view Learn basic and advanced ER modelling techniques.

339 views • 23 slides

ER-to-Relational Mapping Principles Specialization/Generalization

348 views • 22 slides

Chapter 9 Relational Database Design by ER- to-Relational Mapping

Chapter 9 Relational Database Design by ER- to-Relational Mapping. Chapter 9 Outline. Relational Database Design Using ER-to-Relational Mapping. Relational Database Design by ER-to-Relational Mapping. Design a relational database schema Based on a conceptual schema design

396 views • 16 slides

Chapter (9) ER and EER-to-Relational Mapping, and other Relational Languages Objectives

Chapter (9) ER and EER-to-Relational Mapping, and other Relational Languages Objectives How a relational database schema can be created from a conceptual schema developed using the ER models.

614 views • 12 slides