🗄️ SQL Notes – Learn SQL With MySQL

Learn SQL step-by-step with practical queries, database design rules & analytics use-cases for real jobs.

https://github.com/Ashwin18-Offcl/SQL_Notes.git

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🗂 Repository Structure (Planned & Expandable)

SQL_Notes/
 ├── 01_SQL_Basics/
 ├── 02_DDL_Commands/
 ├── 03_DML_Commands/
 ├── 04_Clauses/
 ├── 05_Functions/
 ├── 06_Joins_Keys/
 ├── 07_Subqueries/
 ├── 08_Views/
 ├── 09_StoredProcedures/
 ├── 10_Performance_Queries/
 ├── SQL images/
 └── README.md

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📚 Learning Roadmap (Step-By-Step Notes)

1️⃣ SQL Basics

• What is SQL & DBMS
• Installing MySQL
• Database & Table creation

CREATE DATABASE college;
USE college;

CREATE TABLE students(
   id INT PRIMARY KEY,
   name VARCHAR(50),
   course VARCHAR(50)
);

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2️⃣ DDL Commands (Data Definition Language)

• CREATE, ALTER, DROP, TRUNCATE

ALTER TABLE students ADD marks INT;
DROP TABLE students;

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3️⃣ DML Commands (Data Manipulation Language)

• INSERT, UPDATE, DELETE

INSERT INTO students VALUES (1, 'Ashwin', 'SQL', 88);
UPDATE students SET marks = 90 WHERE id = 1;
DELETE FROM students WHERE id = 1;

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4️⃣ SELECT Queries & Filters (MOST Important)

• WHERE, AND, OR, BETWEEN, IN, LIKE

SELECT name, marks
FROM students
WHERE marks >= 75 AND course = 'SQL';

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5️⃣ Sorting & Limiting Records

SELECT * FROM students ORDER BY marks DESC LIMIT 3;

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6️⃣ SQL Functions

• Aggregate: COUNT, SUM, AVG, MAX, MIN
• String, Date, Math functions

SELECT course, AVG(marks) AS avg_marks
FROM students
GROUP BY course;

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7️⃣ JOINS (Heart of SQL ♥)

• INNER JOIN, LEFT JOIN, RIGHT JOIN, FULL JOIN

SELECT s.name, c.course_name
FROM students s
INNER JOIN courses c
ON s.course_id = c.course_id;

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8️⃣ Subqueries & Nested SELECT

SELECT name FROM students 
WHERE marks > (SELECT AVG(marks) FROM students);

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9️⃣ Views for Reusable Queries

CREATE VIEW TopStudents AS
SELECT name, marks FROM students WHERE marks > 80;

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🔟 Indexing & Performance (Advanced)

CREATE INDEX idx_marks ON students(marks);

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📈 SQL For Data Analytics & BI Tools

This repo also covers: ✔ Analytical queries ✔ Ranking functions ✔ Queries used in Power BI / Tableau ✔ Real-world case studies

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🧩 Skills Practicing in this Repo

• SQL Query Writing
• Database Table Design
• Joins & Relationships
• Analytical Reporting Queries
• Optimization & Indexing
• Problem Solving With Data

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🏷️ Topics / Tags

GitHub Topics: sql, mysql, database, data-analysis, joins, subqueries, sql-notes, learning-notes, tutorial

Social Hashtags: #SQL #MySQL #DataAnalytics #DatabaseDesign #BI #LearningInPublic #AshwinPanbude

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🚀 Continuous updates — More SQL practice sets, interview questions & project tasks coming soon!