SQL Roadmap – Beginner to Advanced

1️⃣ SQL Introduction

Beginner

What is SQL?
What is Database, Table, Row, Column?
Why SQL is required?
Real‑time examples: Banking, E‑commerce, Employee data

2️⃣ SQL Commands

Foundation

DDL – CREATE, ALTER, DROP, TRUNCATE
DML – INSERT, UPDATE, DELETE
DQL – SELECT
TCL – COMMIT, ROLLBACK, SAVEPOINT
DCL – GRANT, REVOKE

3️⃣ SQL Keys & Constraints

Very Important

Primary Key, Foreign Key, Composite Key
NOT NULL, UNIQUE, CHECK, DEFAULT
Ensures data accuracy and integrity

4️⃣ SQL Joins

Core Skill

INNER JOIN
LEFT JOIN
RIGHT JOIN
FULL OUTER JOIN
SELF JOIN
Used to connect multiple tables

5️⃣ SQL Sub Queries

Intermediate

Single Row Subquery
Multi Row Subquery
Correlated Subquery
Used in filtering & complex conditions

6️⃣ SQL CTE (WITH Clause)

Advanced

Simplifies complex queries
Recursive CTE for hierarchy
Improves readability
Used in Data Engineering

7️⃣ SQL Window Functions

High Demand

ROW_NUMBER(), RANK(), DENSE_RANK()
SUM() OVER(), Moving averages
Running totals
Used in BI, Analytics, Big Data

8️⃣ Stored Procedures

Professional

Reusable SQL programs
Performance improvement
Secure business logic
Used for reports & automation

9️⃣ SQL Interview Questions

Placement Ready

WHERE vs HAVING
DELETE vs TRUNCATE
Primary vs Unique Key
CTE vs Subquery
Window Functions vs GROUP BY

🔟 SQL + Python

Real Time

Connect Python to Database
Execute SQL from Python
Use Pandas for data analysis
ETL, Automation, Reporting

Final Learning Flow

Beginner → Basics & Commands
Intermediate → Joins & Subqueries
Advanced → CTE & Window Functions
Professional → Stored Procedures & Python Integration