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SQL

Designing and querying relational databases. From simple SELECT statements to complex JOINs and database design for real applications.

72% — Intermediate

Knowledge

What I Know

📋 SELECT, WHERE, ORDER BY

🔗 INNER / LEFT / RIGHT JOIN

📊 GROUP BY & Aggregates

🏗️ CREATE TABLE & Schema Design

🔑 Primary & Foreign Keys

📝 INSERT, UPDATE, DELETE

🔍 Subqueries

📌 Indexes

💾 SQLite with Python

🔒 Constraints (NOT NULL, UNIQUE)

Projects

Database Projects

🏫

SQL · Database Design

College Management DB

A full relational database design for a college system — students, courses, grades, faculty, and enrollment with normalized tables and proper constraints.

GitHub →

🎮

SQLite · Python

Game Leaderboard DB

SQLite database integrated with Python for storing game scores, player data, and leaderboard rankings for a simple game project.

GitHub →

📊

SQL · Queries

SQL Practice Problems

Collection of solved SQL problems ranging from basic queries to advanced JOINs, subqueries, and window functions.

GitHub →

Code

Sample SQL

SQL

-- College Management Database

CREATE TABLE students (
  id       INTEGER PRIMARY KEY AUTOINCREMENT,
  name     TEXT NOT NULL,
  roll_no  TEXT UNIQUE NOT NULL,
  branch   TEXT NOT NULL,
  year     INTEGER
);

CREATE TABLE courses (
  id       INTEGER PRIMARY KEY,
  name     TEXT NOT NULL,
  credits  INTEGER,
  faculty  TEXT
);

CREATE TABLE enrollments (
  student_id  INTEGER REFERENCES students(id),
  course_id   INTEGER REFERENCES courses(id),
  grade       TEXT,
  semester    TEXT,
  PRIMARY KEY (student_id, course_id)
);

-- Get all students with their courses and grades
SELECT s.name, s.roll_no, c.name AS course, e.grade
FROM students s
JOIN enrollments e ON s.id = e.student_id
JOIN courses c ON c.id = e.course_id
WHERE s.branch = 'IT'
ORDER BY s.name;