SQL Online Playground

How to use the SQL playground#

The playground starts with a small sample database about an online school: students, courses and enrollments. Click a table on the right to see its rows, pick an example query, or write your own and press Run (Ctrl + Enter).

You can also change data with INSERT, UPDATE and DELETE, or create your own tables. Reset database brings back the original sample data.

The sample database#

Table	Columns
students	id, name, city, age
courses	id, title, level, price
enrollments	student_id, course_id, score, enrolled_on

Exercises to try#

1. List students from Delhi, youngest first.
2. Show each course with the number of students enrolled (include courses with nobody: LEFT JOIN).
3. Find the student with the highest average score.
4. Add a new course and enrol two students in it.
5. Which city has the most students?

Stuck? The SQL tutorials explain every clause step by step.

Good to know#

• This is SQLite, running entirely in your browser. Almost everything you learn here works the same in MySQL and PostgreSQL; small differences (like LIMIT vs TOP, or date functions) are explained in the lessons.
• Your last query is remembered on this device. Data changes are lost when you reload the page.