1. Database Architecture Introduction to Databases

2. The Nature of Data Un-structured Semi-structured Structured

3. Semantic Hierarchy of Data Models File-Based Systems Hierarchical Network Relational Object-RelationalObject-Oriented Low Semantics High Semantics 1 st Generation 2 nd Generation 3 rd Generation

4. File-Based System Limitations Separation and Isolation of Data Duplication of Data Data Dependence Incompatible File Formats Issues with Data Security, Proliferation of Application Programs Data Management

5. The Database Management System (DBMS)….what is it? A software system that enables users to define, create, maintain, and control access to the database.

6. Advantages of a Database Management System Views Control of data redundancy Data consistency Sharing of data Improved data integrity Improved security Enforcement of Standards Increased Productivity Improved Maintenance through data independence Increased Concurrency

7. Disadvantages of a Database Management System (DBMS) Complexity Cost Higher Impact of Failures Support Requirements

8. Database Layers of Abstraction Physical Layer Architecture Logical Layer Architecture View Layer Architecture Three Level ANSI-SPARC Architecture

9. Database Languages Structure Query Language (SQL) Data Definition Language Data Control Language Data Manipulation Language Data Definition Language Data Manipulation Language SELECT (Query Language)

10. Data and Meta-data Database DATAMETA-DATA

11. Functions of the DBMS Data storage, retrieval, and update A user-accessible catalog (meta-data) Transaction Support Concurrency Control Recovery Services Authorization Services Support for Data Communication Integrity Services Data Independence Services Utilities

12. Components of the DBMS Transaction Management Query Processing Storage Management Database 1. Schema Modification 2. Data Modification 3. Query 3 Possible Inputs

13. Database Systems The DBMS resides in server memory The physical database resides on disk