Introduction to SQL — What is SQL? — History and standards (SQL-92, SQL:2011) — Popular RDBMS: MySQL, PostgreSQL, SQLite, SQL Server — SQL syntax and structure Database Basics — What is a database? — Tables, rows, columns — Primary key and foreign key — Relational model overview Creating and Managing Databases — CREATE DATABASE — USE, DROP DATABASE — Database naming conventions Creating and Managing Tables — CREATE TABLE syntax — Data types (INT, VARCHAR, DATE, etc.) — Constraints (NOT NULL, UNIQUE, DEFAULT) — DROP and ALTER TABLE Inserting Data — INSERT INTO syntax — Inserting single and multiple rows — Using DEFAULT values Querying Data (SELECT) — SELECT basics — Filtering with WHERE — Sorting with ORDER BY — DISTINCT keyword — LIMIT and OFFSET Filtering Data — Comparison operators (=, <>, >, etc.) — Logical operators (AND, OR, NOT) — BETWEEN, IN, LIKE — IS NULL / IS NOT NULL Updating and Deleting Data — UPDATE syntax — DELETE syntax — WHERE clause best practices — TRUNCATE vs DELETE Joins in SQL — INNER JOIN — LEFT JOIN — RIGHT JOIN — FULL OUTER JOIN — Self join and cross join Aggregate Functions — COUNT(), SUM(), AVG(), MIN(), MAX() — GROUP BY and HAVING — Filtering grouped data Subqueries — Subqueries in SELECT, WHERE, FROM — Correlated vs non-correlated subqueries Set Operations — UNION vs UNION ALL — INTERSECT and EXCEPT (if supported) Indexes — What is an index? — CREATE INDEX syntax — Unique index — Performance considerations Constraints and Keys — PRIMARY KEY — FOREIGN KEY — CHECK, DEFAULT — ON DELETE / ON UPDATE CASCADE Views — CREATE VIEW syntax — Updating data through views — Dropping views Stored Procedures — What is a stored procedure? — CREATE PROCEDURE — IN, OUT, INOUT parameters — Calling procedures Functions — User-defined functions (UDFs) — Differences from procedures — RETURN values and syntax Triggers — CREATE TRIGGER syntax — BEFORE / AFTER INSERT, UPDATE, DELETE — Use cases and examples Transactions and ACID — BEGIN, COMMIT, ROLLBACK — SAVEPOINT — Understanding ACID properties User and Permission Management — Creating users — GRANT and REVOKE privileges — Roles and security best practices Normalization and Database Design — 1NF, 2NF, 3NF — Denormalization — Designing efficient schemas Working with Dates and Time — DATE, TIME, DATETIME — DATE functions (NOW(), CURDATE(), DATEDIFF()) Common Built-in Functions — String functions (CONCAT, SUBSTRING, REPLACE) — Math functions (ROUND, FLOOR, CEIL) — Date functions (NOW, DATE_ADD, etc.) Performance Tuning — Query optimization — Using EXPLAIN — Reducing slow queries Real-World Projects — Student/course database — E-commerce schema — Blog or CMS backend — Library/book management system