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(641 Week 3 Outline) (by Liping Liu) Review: Course and Sections (why splits), Course and Prerequisites (Two entities or one?), Grade (where to store it), minimum grade required for prerequisites
Lecture 1: Forward Engineering: ERD to Relational Model: (Remember these rules, Chapter 6 of LIU)
Each entity set is converted into a table with its attributes as the columns of the table
Depending on the mapping cardinality, you modify the tables to make them related
If the relationship is 1:m or m:1, you put the primary key of the table for one-side entity set into the table for the many-side entity set
If the relationship is m:m, you build a junction table which has the primary keys of both entity sets as columns
If the relationship is 1:1, you can put the primary key of one entity set into the table for another entity set... more >>
(324: Review I for Database Midterm on 9-23-26) (by Liping Liu) Concepts:
Databases
DBMS
Logical Data Models
Hierarchical Models
Network Models
Relational Models
Primary key
Foreign Key
Referential Integrity Rules
Entities
Relationships
Mapping Cardinality
Optionality
Attributes
Composite Attributes
Multi-valued Attributes
Relations
Relational Models
Recursive Relationships
Weak Entities
Super and Sub Entities
Gerund
SQL
Constraints
Oracle Meta Tables
Oracle Data Types
Skills and Techniques:
Conceptual Data Modeling (Entity-Relationship Diagramming) from the understanding of business objects and their relationships or from forms, reports, tables, and other data carrier to understand data requirements... more >>
This system is designed and developed by Professor Liping Liu with financial support from Southern Illinois University at Carbondale. It evolved from a prior version called CourseWeb (for courses prior to Year 2000) and UXTEND.COM and www.e-course.org.
