2. Database Overview

File-Based System

Stores data in separate files managed by individual applications.

Data

Raw facts that have not been processed.

Field

Single piece of data, such as a customer name.

Record

Collection of related fields describing a person, place, or thing.

File

Collection of related records.

Data Redundancy

Unnecessary duplication of data in multiple locations.

Data Inconsistency

Different values for the same data across locations.

Data Dependence

Changes in data storage characteristics affect programs.

Data Independence

Data storage characteristics can change without affecting programs.

Structural Dependence

Changing a file's structure requires program changes.

Structural Independence

File structure can change without affecting programs.

File-Based System Limitations

Data redundancy, inconsistency, limited sharing/security, dependence, and lengthy development.

Data Anomaly

Problem caused when changes to redundant data are not completed correctly.

Insertion Anomaly

Cannot add new data without adding unrelated information.

Update Anomaly

Same information must be updated in multiple places.

Deletion Anomaly

Deleting data unintentionally removes other important information.

Database

Shared, integrated computer structure that stores data.

End-User Data

Raw facts that are important to users.

Metadata

Data about data; describes characteristics and relationships.

System Catalog

Stores metadata about the database.

Information

Processed data that provides meaning and context.

Good Information

Accurate, relevant, and timely.

Ubiquitous Data

Data is abundant and everywhere.

Pervasive Data

Data is widespread and persistent.

Single-User Database

Supports one user at a time.

Multiuser Database

Supports multiple users simultaneously.

Workgroup Database

Supports a small group or department.

Enterprise Database

Supports users across many departments.

Centralized Database

Stores data at a single location.

Distributed Database

Stores data across multiple locations.

Cloud Database

Created and maintained using cloud data services.

General-Purpose Database

Stores data across multiple subject areas.

Discipline-Specific Database

Focuses on a particular subject area.

Operational Database

Supports an organization's daily operations.

Data Warehouse

Stores data optimized for analysis and decision-making.

OLAP (Online Analytical Processing)

Analyzes and models data in a data warehouse.

Business Intelligence (BI)

Processes business data to support decision-making.

Structured Data

Data organized into a defined format.

Unstructured Data

Data in its original raw state.

Semistructured Data

Data that has been partially organized.

NoSQL (Not Only SQL)

Handles large amounts of structured and unstructured data.

DBMS

Software that manages database structure, controls access, and connects users to the database.

Database System Components

Hardware, software, people, procedures, and data.

Data Dictionary Management

Stores definitions of data elements and their relationships.

Data Storage Management

Manages data storage and performance.

Security Management

Protects data and controls user access.

Multiuser Access Control

Allows simultaneous access without compromising data integrity.

Backup and Recovery Management

Restores the database after a failure.

Data Integrity Management

Minimizes redundancy and maximizes consistency.

SQL

Structured Query Language; standard language for accessing and querying databases.

DBMS Advantages

Improved data sharing, security, consistency, integration, and decision-making.

DBMS Disadvantages

Higher costs, complexity, maintenance, vendor dependence, and upgrades.

Database Design

Creating a flexible structure to store and manage data.

Generative AI

Uses learned patterns from input data to generate new content.

Machine Learning

Uses statistical techniques to identify patterns and predict trends.

Natural Language Processing (NLP)

AI that processes human language.

AI Challenges

Ethical concerns, data privacy, inherited bias, and resource utilization.