erd to relational schema in DBMS of module 1

erd to relational schema in DBMS of module 1

1. Database Management System ER Diagram → Relational Schema

2. Design Phases 2 Physical- design Phase (Relational Database) Logical- design Phase (Relational Schema) Conceptual- design Phase (ER Diagíam) Useí Requiíements Specification

3. Database Schema & Data Model Database Schema Descíibes the oveíall design of the database at diffeíent levels(physical, logical, view) Data Model Descíibes a way to design database at physical, logical and view level. It is a collection of conceptual tools and languages foí descíibing data, data íelationships, data semantics, and consistency constíaints. High- level conceptual data model  ER Model Recoíd based logical data model  Relational Model 3

4. E- R Diagram vs Relational Schema 4 ER Diagíam Relational Schema ľkc mai⭲ compo⭲c⭲ts or ER Modcl aíc: E⭲titQ Sct – sct or similaí c⭲titics Rclatio⭲skip Sct – sct or similaí íclatio⭲skips Attíib"tcs – i⭲cl"di⭲g dirrcíc⭲t tQpcs or kcQs ľkc mai⭲ compo⭲c⭲ts or Rclatio⭲al Modcl aíc: Rclatio⭲s (tablcs) ľ"plc (íow, "⭲oídcícd) Attíib"tcs (col"m⭲s, "⭲oídcícd) Komai⭲ (col"m⭲ tQpc) PíimaíQ KcQ Ioícig⭲ KcQ ER Modcl dcscíibcs Mappi⭲g Caídi⭲alitQ. Rclatio⭲al Modcl docs ⭲ot dcscíibc Mappi⭲g Caídi⭲alitQ.

5. E- R Diagram vs Relational Schema 5 ER Diagram : Relational Schema :

6. Relational Schema >> Strong Entity Set G

7. Relational Schema >> Weak Entity Set 7

8. Relational Schema >> Composite Attribute 8

9. Relational Schema >> Multivalued Attribute 9

10. Relational Schema >> Derived Attribute 10

11. Relational Schema >> One to One Relationship Set 11 Nullable

12. Relational Schema >> One to Many Relationship Set 12 Nullable

13. Relational Schema >> Many to Many Relationship Set 13

14. Relational Schema >> Recursive Relationship Set 14

15. Relational Schema >> Identifying Relationship Set 15

16. E- R Diagram → Relational Schema 1G