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Data Storage Disk Storage Devices Files of Records Operations on Files Unordered Files Ordered Files Hashed Files RAID Technology Indexing Structures for Files Types of Single-level Ordered Indexes Multilevel Indexes Dynamic Multilevel Indexes Using B-Trees and B+-Trees Indexes on Multiple Keys

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Introduction: “goodness” measures for relations Functional dependencies (FDs) Definition of FD Direct, indirect, partial dependencies Inference Rules for FDs Equivalence of Sets of FDs Minimal Sets of FDs Normalization 1NF and dependency problems 2NF – solves partial dependency 3NF – solves indirect dependency BCNF – well-normalized rela...

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SQL developments: an overview SQL DDL: Create, Alter, Drop DML: select, insert, update, delete Introduction to advanced DDL (assertions & triggers), views, DCL (commit, rollback, grant, revoke)

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Brief Introduction to Relational Calculus Another variation of relational calculus called the domain relational calculus, or simply, domain calculus is equivalent to tuple calculus and to relational algebra QBE (Query-By-Example): see Appendix D Domain calculus differs from tuple calculus in the type of variables used in formulas: rather than ha...

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File-based Approach Database Approach Three-Schema Architecture and Data Independence Database Languages Data Models Database Schema and Database State Data Management Systems Framework (where are we?) Next week: ER Model

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Summary Relational Data Model Basic Concepts Relational Integrity Constraints: key, primary & foreign keys, entity integrity constraint, referential integrity Update Operations on Relations ER/EER-to-Relational Mapping 3 Main Phases of Database Design: An Overview Conceptual Database Design: A Summarization Logical Database Design ER- & EE...

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Summary EER model Limitations of Basic Concepts of the ER Model Enhanced-ER (EER) Model Concepts Subclasses and Superclasses Specialization and Generalization Specialization / Generalization Hierarchies, Lattices and Shared Subclasses Categories Formal Definitions of EER Model Database Design Modeling Tools Next week: Relational model & ...

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Summary What is ER Model? And Why? Overview of Database Design Process Example COMPANY Database ER Model Concepts ER Diagram Alternative Diagrammatic Notations (UML) Problems with ER Models Next week: EER Reading: [1] Chapter 4 [2] Chapter 12

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TRANSFORM CLASS DIAGRAM TO RELATIONAL DATABASE SCHEMA In general, the transformation of class diagram to relational schema is similar to that of EER to relational schema, except some specific issues. 1.  Transform a class in class diagram to a table 2.  Transform an attribute of a class to a table column. 3.  In case a class does not have a...

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A multidatabase system is a special distributed database system where one node may be running relational database system under Unix, another may be running object-oriented system under Window and so on. A transaction may run in a distributed fashion at multiple nodes. In this execution scenario the transaction commits only when all these multiple n...

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