All_Data_DBMS_MODELS 130725130028-phpapp01
- 1. All Data models in DBMS Submitted By- Submitted To-
- 2. Overview • Data • Information • Database • Data Model Types of Data Model 1. Record Base model • Relationship model • Network Model • Hierarchical Model 2.Entity Relationship Model 3.Object-Oriented Model
- 3. A data is known as the row fact which is stored in computers memory and used by the user as the output. Example-21. Data
- 4. Information Collection of data its called information. Example-House no 21C-S-1,Sch No 78 Indore
- 5. Database A collection of inter related data its called database.
- 6. Data Model A data model is a collection of concepts that can be used to describe the structure of a database.
- 7. Types of Data Models 1.Record Base model
- 8. Types of Data Models 1.Record Base model • A record based data model is used to specify the overall logical structure of the database. • Each record type defines a fixed no. of fields having a fixed length.
- 9. Relational model • In the relational model, data is organized in two-dimensional tables called relations.
- 10. Relations No Course-Name Unit CIS15 Intro to C 5 CIS17 Intro to Java 5 CIS19 UNIX 4 CIS51 Networking 5 Attributes Tuples
- 11. • Attributes. Each column in a relation is called an attribute. Relations • Tuples Each row in a relation is called a tuple. A tuple defines a collection of attribute values.
- 12. Network Model In the network model, the entities are organized in a graph, in which some entities can be accessed through several paths No Name ID Name Course No Name Unit ID Name DEPARTMENT COURSES STUDENTS PROFESSORS
- 13. Hierarchical Model The hierarchical data model organizes data in a tree structure
- 14. PROFESSORS No Name ID Name Course No Name Unit ID Name DEPARTMENT COURSES STUDENTS Hierarchical Model
- 15. 2.Entity Relationship Model • The E-R (entity-relationship) data model views the real world as a set of basic objects (entities) and relationships among these objects ER Model Basics •Entity •Entity Set •Attributes •Relationship
- 16. Entity • entity is a thing in the real world with an independent existance. and entity set is collection or set all entities of a particular entity type at any point of time.