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ODBMS also known as Object-Oriented Database Management Systems (OODBMS)
Examples
db4o, Caché, eXtremeDB, Perst, Objectivity/DB, ObjectStore, Versant Object Database, ObjectDB, VOSS
Object-Oriented Concepts
Class (Template, like a cookie cutter)
Properties (attributes) / Behaviors (actions/methods)
Access/Visibility to properties and behaviors
Object (a cookie cut into the memory dough)
An instance of a class
Encapsulation
Storing an object’s properties and behaviors together as part of the instance
Relationships
Inheritance (Single, Multiple) / Inheritance Hierarchy Object Database Model Object Database Model Person Class Properties Behaviors SSN, Name, Birthdate getSSN, setSSN, getName, setName, getBirthdate, setBirthdate, getAge Employee Class Properties Behaviors Org, Dept, Title, Mgr, EmployeeID, HireDate getOrg, setOrg, getDept, setDept, getTitle, setTitle, getEmployeeID, setEmployeeID, getMgr, setMgr, getReportingHierarchy, getDirectReports, getCoworkers, getHireDate, setHireDate Object Class Properties Behaviors ObjectID getID, setID IS-A IS-A OODBMS are integrated with an object-oriented programming language similar to RDBMS but with
an object-oriented database model. Objects, classes, and inheritance are directly supported in the database schemas and in the query language. 21
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