Data Models In Database Management System

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    16-Jul-2015

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All Data models in DBMSOverviewData Information Database Data Model Types of Data Model Record Base model Relationship modelNetwork ModelHierarchical Model2.Entity Relationship Model3.Object-Oriented ModelPrepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar2A data is known as the row fact which is stored in computers memory and used by the user as the output. Example-21.DataInformationCollection of data its called information.Example-House no 21C-S-1,Sch No 78 IndoreDatabaseA collection of inter related data its called database.Data Model A data model is a collection of concepts that can be used to describe the structure of a database.Types of Data Models1.Record Base model Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar7Types of Data Models1.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. Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar8Relational modelIn the relational model, data is organized in two-dimensional tables called relations.Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar9RelationsNoCourse-NameUnitCIS15Intro to C5CIS17Intro to Java5CIS19UNIX4CIS51Networking5AttributesTuplesPrepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar10Attributes. Each column in a relation is called an attribute.RelationsTuples Each row in a relation is called a tuple. A tuple defines a collection of attribute values.Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar11Network ModelIn the network model, the entities are organized in a graph, in which some entities can be accessed through several paths NoNameIDNameCourseNoNameUnitIDNameDEPARTMENTCOURSESSTUDENTSPROFESSORSPrepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar12Hierarchical ModelThe hierarchical data model organizes data in a tree structurePROFESSORSNoNameIDNameCourseNoNameUnitIDNameDEPARTMENTCOURSESSTUDENTSHierarchical ModelPrepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar142.Entity Relationship ModelThe E-R (entity-relationship) data model views the real world as a set of basic objects (entities) and relationships among these objectsER Model BasicsEntityEntity SetAttributesRelationshipPrepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar15Entityentity 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.Prepared By Amad Ahmad BSSE 5th Semester Abasyn University Peshawar16

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