DBMS 3 | ER Diagram to Relational Schema
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The document outlines the design phases of a database management system, including the conceptual, logical, and physical design stages through ER diagrams and relational schemas. It distinguishes between the components of the ER model and the relational model, emphasizing their unique features and relationships. Additionally, it provides references for further reading on database systems.
DBMS 3 | ER Diagram to Relational Schema
- 1. Database Management System ER Diagram → Relational Schema Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 2. Design Phases 2 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU Physical-design Phase (Relational Database) Logical-design Phase (Relational Schema) Conceptual-design Phase (ER Diagram) User Requirements Specification
- 3. Database Schema & Data Model Database Schema Describes the overall design of the database at different levels(physical, logical, view) Data Model Describes a way to design database at physical, logical and view level. It is a collection of conceptual tools and languages for describing data, data relationships, data semantics, and consistency constraints. High-level conceptual data model → ER Model Record based logical data model → Relational Model 3 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 4. E-R Diagram vs Relational Schema 4 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU ER Diagram Relational Schema The main components of ER Model are: • Entity Set – set of similar entities • Relationship Set – set of similar relationships • Attributes – including different types of keys The main components of Relational Model are: • Relations (tables) • Tuple (row, unordered) • Attributes (columns, unordered) • Domain (column type) • Primary Key • Foreign Key ER Model describes Mapping Cardinality. Relational Model does not describe Mapping Cardinality.
- 5. E-R Diagram vs Relational Schema 5 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU ER Diagram : Relational Schema :
- 6. Relational Schema >> Strong Entity Set 6 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 7. Relational Schema >> Weak Entity Set 7 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 8. Relational Schema >> Composite Attribute 8 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 9. Relational Schema >> Multivalued Attribute 9 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 10. Relational Schema >> Derived Attribute 10 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 11. Relational Schema >> One to One Relationship Set 11 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU Nullable
- 12. Relational Schema >> One to Many Relationship Set 12 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU Nullable
- 13. Relational Schema >> Many to Many Relationship Set 13 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 14. Relational Schema >> Recursive Relationship Set 14 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 15. Relational Schema >> Identifying Relationship Set 15 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 16. E-R Diagram → Relational Schema 16 Mohammad Imam Hossain, Lecturer, Dept. of CSE, UIU
- 17. 17 THANKS! Any questions? Email : [email protected] References: ▪ Database System Concepts by S. Sudarshan, Henry F. Korth, Abraham Silberschatz ▪ Database Systems The Complete Book by Ullman, Widom and Hector ▪ https://www.lucidchart.com/pages/er-diagrams ▪ https://www.vertabelo.com/blog/chen-erd-notation/