M
MJJ Tools

Online SQL Compiler

Write, test, and execute SQL queries online. Practice SQL with sample databases, experiment with different queries, and learn database concepts in an interactive environment.

Database Schema

📋 employees
idINTEGER 🔑
first_nameTEXT
last_nameTEXT
emailTEXT
departmentTEXT
salaryINTEGER
hire_dateDATE
8 rows
📋 departments
idINTEGER 🔑
nameTEXT
budgetINTEGER
manager_idINTEGER
4 rows
📋 projects
idINTEGER 🔑
nameTEXT
start_dateDATE
end_dateDATE
budgetINTEGER
department_idINTEGER
4 rows

Sample Queries

SQL Editor

Lines: 11 | Characters: 233
Tip: Use semicolon (;) to separate multiple queries

SQL Reference

Basic Queries:

  • SELECT * FROM table_name;
  • SELECT col1, col2 FROM table_name;
  • WHERE condition
  • ORDER BY column ASC/DESC
  • GROUP BY column
  • HAVING condition

Functions & Operators:

  • COUNT(), SUM(), AVG(), MIN(), MAX()
  • =, !=, <, >, <=, >=
  • AND, OR, NOT
  • LIKE, IN, BETWEEN
  • IS NULL, IS NOT NULL

Note: This is a demo SQL compiler running client-side with sample data. Advanced SQL features and real database connections are not available. Perfect for learning and testing basic SQL queries!