Run SQL queries online with our SQL compiler. Practice SQL with sample databases and get instant results.
Click "Run SQL" to execute the SQL statement above.
Database loaded with sample tables.
Feel free to experiment with any SQL statement.
SQL is probably the most consistently useful skill you can have as a developer, analyst, or anyone who works with data. The problem is that getting a working SQL environment set up locally is surprisingly annoying — you need to install a database server, create a user, configure permissions, create a schema, load some data, and then you can finally start writing queries. That's a lot of friction just to practice a SELECT statement.
This free online SQL editor with sample database skips all of that. The page loads with three pre-built tables — customers, orders, and products — already populated with realistic data. Type a query, hit Run SQL or press Ctrl+Enter, and see the results in the table on the right immediately. No database installation, no user configuration, no schema setup.
The database has three tables that relate to each other in realistic ways, which is important for practicing the kinds of queries that actually come up in real work.
Customers — 20 records with name, email, phone, city, country, created_at date, and status. Enough variety to make GROUP BY and WHERE queries interesting without being overwhelming. Orders — 20 records with customer_id, product_id, quantity, amount, order_date, and status. Linked to customers via customer_id so you can practice JOIN queries. Products — 10 records with name, category, price, stock, and rating. Used in both the orders table and standalone queries.
The fact that the tables are linked is what makes this a proper SQL practice environment with relational tables for JOIN practice rather than just a calculator that runs SELECT statements on flat data. You can write real JOIN queries that pull customer names alongside their order totals, or find products that have never been ordered.
Basic SELECT and WHERE — Start with SELECT * FROM customers LIMIT 10 to see the structure. Add a WHERE status = 'Active' clause to filter. Change it to WHERE city = 'New York'. These are the foundational patterns for SQL WHERE clause practice with real data online and they build the muscle memory you need for everything more complex.
GROUP BY and aggregation — The Quick Queries panel has a "Products by Category" button that runs SELECT category, COUNT(*) as product_count FROM products GROUP BY category. This is a genuinely useful pattern — you'll use GROUP BY constantly in real database work. Add HAVING COUNT(*) > 1 to filter the groups. Add ORDER BY product_count DESC to sort by most common category. These modifications teach you how the clauses interact. This kind of interactive SQL GROUP BY and aggregation functions practice tool is what turns theoretical knowledge into actual skill.
JOIN queries — Write SELECT customers.name, orders.amount, orders.order_date FROM customers INNER JOIN orders ON customers.id = orders.customer_id to pull customer names alongside their orders. Change INNER JOIN to LEFT JOIN and notice how customers without orders now appear with NULL values in the order columns. This difference — understanding what LEFT JOIN actually does differently than INNER JOIN — is one of the things that separates people who can write SQL from people who can write it well. Practicing SQL JOIN queries online with customers and orders tables with immediate visual feedback makes this click much faster than reading about it.
Subqueries and filtering on aggregates — Try finding customers who have spent more than the average order amount using a subquery. Or find the customer who placed the most orders using a subquery in the WHERE clause. The immediate feedback from an online SQL compiler for subquery and nested query practice makes debugging these much faster than working in a local environment where you might be scrolling through terminal output.
CS and data students — Your database course probably has you connecting to a remote server that's slow, or installing something locally that took three class periods to get working. This just works. Load the page, start writing queries. It's a practical online SQL editor for database students with no setup required that lets you focus on learning the language rather than fighting infrastructure.
Developers learning SQL for the first time — You understand programming logic but you've never written SQL before. The Quick Queries panel gives you working examples to start from. Click "Customers by City," see the query that runs, see the output, then modify it. Change GROUP BY city to GROUP BY country. Add a HAVING clause. This learn-by-modification approach works well for programmers. It's the kind of SQL query tester for web developers learning database queries that fits how developers already learn.
Analysts preparing for interviews — SQL interview questions almost always involve JOINs, GROUP BY, window functions, and subqueries. Being able to quickly test your query logic and verify the output format before your interview is genuinely useful. Using an online SQL practice environment for data analyst job interview preparation to run through common question patterns is faster and less friction than spinning up a local database.
People who need to verify query logic quickly — You're working on a project and you want to verify that a particular JOIN or aggregation does what you think it does before putting it in your actual codebase. Running it here against the sample data to confirm the structure of the output takes 30 seconds. Much faster than setting up a test scenario in your development database.
The Export Excel button converts whatever is currently showing in the results table to a CSV file and downloads it. CSV opens in Excel, Google Sheets, and any spreadsheet tool. This is useful if you're running exploratory queries and want to save the results for further analysis, share them with someone, or paste them into a report. It works as a simple online SQL query results exporter to CSV and Excel format for quick data extraction.
The most important shortcut: Ctrl+Enter runs the current query without reaching for the mouse. For anyone writing multiple queries in a session, this makes the workflow considerably faster. Write a query, Ctrl+Enter, see the result, modify, Ctrl+Enter again. It's the kind of tight feedback loop that makes learning SQL by doing actually productive rather than tedious.
Can I create my own tables and insert data? Yes — CREATE TABLE, INSERT INTO, UPDATE, and DELETE statements all work. The database runs in-memory via sql.js, so your custom tables exist for the duration of your browser session. If you refresh the page, the database resets to the original sample tables. This makes it work well as a browser-based SQL sandbox for creating and querying custom tables.
Does it support MySQL or PostgreSQL syntax? The engine uses SQLite (via sql.js), which covers the core SQL standard. Most SELECT, JOIN, GROUP BY, subquery, and aggregate function syntax that you'd write in MySQL or PostgreSQL works correctly here. SQLite-specific limitations apply — for example, it doesn't support the full range of window functions that PostgreSQL has. For standard SQL learning and practice, the compatibility is solid.
What if my query returns an error? The error message from the SQL engine appears in the results panel with a red highlight. SQLite error messages are usually clear — "no such table," "syntax error near," "no such column" — and tell you exactly what went wrong. This makes it a functional SQL syntax error checker and debugger online for catching and understanding mistakes.
Can I run multiple queries at once? Yes — separate queries with semicolons and the editor will run each one in sequence, displaying results for each. This is useful for workflows where you want to create a table, insert data, and then query it in one go.
Does it work on mobile? The layout is responsive and queries run correctly on mobile browsers. Writing complex SQL on a phone keyboard is awkward, but running existing queries and viewing results works fine on mobile devices.
Write your queries, see your results, learn by doing. No installation, no login, no database server to manage. Just SQL.