Database Management Systems Overview

Database Management Systems (DBMS)

• Databases store structured data using tables and fields.
• Databases save physical space compared to paper records.
• Multiple users can access the same data simultaneously.
• Queries (filters) allow retrieving specific data.

Data vs. Information

• Data is a collection of facts, meaningless on its own.
• Information puts data into context, making it understandable.

Database vs. Spreadsheet

• Spreadsheets manipulate data with formulas and calculations.
• Databases store data, often with relationships between tables, and allow user-friendly queries.
• Databases generally hold more data than spreadsheets.

Database vs. Information System

• A database can be part of an information system's backend.
• An information system (IS) handles collecting, processing, storing, and distributing information.
  • Includes aspects of task, people, structure, and technology.
• The database provides data used by the information system, which then transforms the data into useful information.

Database Management System (DBMS)

• Software managing a database.
• Can encompass various software/applications (complete DBMS) or a single software (basic database).
• Provides data manipulation tools, security, and built-in data validation.

Data Consistency and Integrity

• Data consistency ensures data within a category is in the same format.
• E.g., date of birth formats (DD/MM/YYYY vs. MM/DD/YYYY).
• Data integrity ensures data is correct, relevant, accurate, and up-to-date.
• Use input methods (like calendars and drop-down menus) to improve data consistency.
• Validation rules within the database enhance consistency.
• Example: using drop-down lists in input forms to control data format and reduce errors.

Database Transaction

• A series of steps to make a single change to the database (update, delete, add).
• Includes ensuring data consistency, running validations, and checking data integrity.