Introduction to Databases and Data Concepts

What is a Database?

• A database is a collection of logically related information, organized for easy access, management, and updates.
• Databases are typically accessed electronically through a computer system.
• A database management system (DBMS) controls access to the database.

What is Data?

• Refers to pieces of information or facts related to an object.
• Example: A person's name, age, height, weight, ethnicity, hair color, and birthdate.

Key terms related to Data & Database

• Field: Most detailed information about events, people, objects, or transactions.
• Record: Collection of related fields.
• Table: Collection of related records with a unique table name.
• Database: Collection of related tables.

Databases in Enterprises

• Businesses use internal and external databases.
• Internal databases: Used for operational activities within the organization, including accounting, sales, finance, and Human Resources.
• Data warehouses: Store data from different sources, primarily used for business intelligence and analysis, not routine operations.

Components of a Database

• Hardware: Physical devices (computers, hard disks) providing interface between computers and real-world systems.
• Software: Programs that manage and control the database, including database software, operating system, network software, and applications that access the data.
• Data: Raw facts and information requiring organization and processing for meaning.
• Procedures: Instructions within a database management system, including setup, login, logout, day-to-day operations, backups, and report generation.
• Database Access Language: Commands to access, update, and delete data stored in a database. Allows users to create databases, tables, insert and delete data.

What is a Database Management System (DBMS)?

• A collection of programs enabling users to access, manipulate, maintain, report, and relate data within a database.
• Used to reduce data redundancy, share data in a controlled manner, and minimize data integrity problems.
• Structured Query Language (SQL) is the standard interface for relational databases, supported by all relational DBMS software.

Components of a DBMS

• Storage engine: Core component interacting with the file system.
• Query language: Enables interaction, from database creation to data insertion and retrieval.
• Query processor: Interprets user requests, transforming them into actionable commands understood by the database.
• Optimization engine: Analyzes database performance and optimizes database and query execution.
• Metadata catalog: Centralized inventory of all database objects, recording metadata when objects are created.
• Log manager: Tracks all DBMS activity, including user logins, database functions, backups, and restorations.
• Reporting & monitoring tools: Generate reports and provide insights into database usage, performance, and resource consumption.