Database and SQL Guide

A concise guide to relational databases and SQL commands, structured for quick reference and study. Ideal for students, developers, or anyone looking to reinforce core database knowledge.

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📚 Contents

• Introduction
• Database Basics
• RDBMS Overview
• Keys and Relationships
• Entity-Relationship Diagram (ERD)
• SQL Command Types
• Data Integrity and Normalization
• Backup and Restore Procedures
• Constraints and Indexing

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🧑‍💻 Introduction

This guide provides a structured approach to understanding and memorizing relational database concepts and SQL commands. Use it as a quick reference or study resource for core topics.

📂 Database Basics

Covers what databases are, types of Database Management Systems (DBMS), and why databases are essential for organized data storage and management.

🔗 RDBMS Overview

Introduces Relational Database Management Systems (RDBMS), explaining table structures, columns, rows, and their interrelationships. This section is essential for grasping the foundation of data organization.

🔑 Keys and Relationships

Summarizes the different types of keys (primary, foreign) and their roles in relational databases. Understanding these keys is crucial for mastering data linking and integrity concepts.

📊 Entity-Relationship Diagram (ERD)

ERDs are visual tools to plan database structures. This section outlines ERD basics and relationships between entities, helping in visualizing and structuring data.

📜 SQL Command Types

Breaks down SQL into different command categories for easy memorization:

• DDL (Data Definition Language): Commands like CREATE, ALTER, DROP for defining database structures.
• DML (Data Manipulation Language): Commands like INSERT, UPDATE, DELETE for modifying data.
• DCL (Data Control Language): Commands like GRANT, REVOKE for access control.
• TCL (Transaction Control Language): Commands like COMMIT, ROLLBACK for transaction management.
• DQL (Data Query Language): Mainly SELECT for querying data.

🛠 Data Integrity and Normalization

Focuses on concepts like normalization to reduce data redundancy and integrity rules that ensure data accuracy and consistency.

💾 Backup and Restore Procedures

These are the basic commands for database backup, differential backup, and restore. Knowing these ensures that data can be safely preserved and recovered.

⚙️ Constraints and Indexing

Overview of constraints (primary key, foreign key, unique, etc.) to enforce data rules and indexing techniques for faster data retrieval.

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📌 Usage

This guide is structured for easy reference and memorization of SQL and database concepts. Ideal for preparing for exams, interviews, or refreshing core database knowledge.

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Created by:

• [Makrious Ayman]
• [For Contact: +20 1205665198]
• [GitHub Profile Link]

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Happy Learning!