AlaSQL for LiaScript: Teach SQL and Query CSV Data in the Browser

SQL is not only for relational databases. With the AlaSQL template, you can run SQL queries inside LiaScript courses against in-memory tables, JavaScript arrays, and CSV files — entirely in the browser.

No backend, no installation, no accounts. Just import the template and start writing SQL.

What is AlaSQL?

AlaSQL is a lightweight, JavaScript-native SQL interpreter. Unlike traditional database engines ported to WebAssembly, AlaSQL is written directly in JavaScript and runs without any binary runtime.

It supports a large subset of standard SQL — CREATE TABLE, INSERT, SELECT, JOIN, GROUP BY, ORDER BY, subqueries — and extends it with the ability to query JavaScript arrays, JSON objects, CSV files, localStorage, and IndexedDB.

The LiaScript AlaSQL template wraps this into two focused macros that integrate cleanly with LiaScript code blocks.

Quick Start

Add this line to your course header:

<!--
import: https://raw.githubusercontent.com/liaTemplates/AlaSQL/master/README.md
-->

All macros are now available throughout the document.

Basic SQL: @AlaSQL.eval

Add @AlaSQL.eval after any SQL code block to make it executable and editable. The block is sent to the AlaSQL interpreter and the result is displayed below as formatted JSON.

``` sql
CREATE TABLE students (id INT, name STRING, grade INT);

INSERT INTO students VALUES (1, 'Alice', 92);
INSERT INTO students VALUES (2, 'Bob',   78);
INSERT INTO students VALUES (3, 'Carol', 85);

SELECT * FROM students ORDER BY grade DESC;
```
@AlaSQL.eval

Try it live:

Persistent State Across Blocks

AlaSQL maintains its own runtime environment within a course page. Tables created in one block are available in all subsequent blocks on the same page — no need to recreate data for every query.

``` sql
CREATE TABLE products (id INT, name STRING, price FLOAT, category STRING);

INSERT INTO products VALUES (1, 'Laptop',  999.00, 'Electronics');
INSERT INTO products VALUES (2, 'Desk',    249.00, 'Furniture');
INSERT INTO products VALUES (3, 'Monitor', 399.00, 'Electronics');
INSERT INTO products VALUES (4, 'Chair',   189.00, 'Furniture');
INSERT INTO products VALUES (5, 'Tablet',  549.00, 'Electronics');
```
@AlaSQL.eval

``` sql
-- Subsequent block — table is already there
SELECT category, COUNT(*) AS items, ROUND(AVG(price), 2) AS avg_price
FROM products
GROUP BY category
ORDER BY avg_price DESC;
```
@AlaSQL.eval

This is useful for multi-step exercises where each block builds on the previous one.

CSV Import: @AlaSQL.eval_with_csv

@AlaSQL.eval_with_csv is the standout feature of this template. It accepts two consecutive code blocks: the first contains a SQL statement (use ? as a placeholder for the data), the second contains the raw CSV with a header row. PapaParse handles the CSV parsing automatically.

``` sql
CREATE TABLE sales;
INSERT INTO sales SELECT * FROM ?;
```
``` text -data.csv
Region,Country,Item,Units,Revenue
Europe,Germany,Laptop,12,11988.00
Europe,France,Tablet,8,4392.00
Asia,Japan,Monitor,15,5985.00
Americas,USA,Laptop,22,21978.00
Asia,India,Tablet,19,10431.00
Americas,Canada,Desk,7,1743.00
Europe,Spain,Chair,11,2079.00
```
@AlaSQL.eval_with_csv

After the import you can query the table in any following block with @AlaSQL.eval:

``` sql
SELECT Region, SUM(Revenue) AS total
FROM sales
GROUP BY Region
ORDER BY total DESC;
```
@AlaSQL.eval

Try the full flow live:

Full Template Demo

The complete AlaSQL README is itself a self-documenting LiaScript course — explore all macros and examples live:

Use Cases

SQL fundamentals — Teach SELECT, WHERE, JOIN, GROUP BY, and aggregation functions with live, editable exercises. No DBMS to install, no accounts to create — students open the course URL and write SQL immediately.

Data literacy with CSV — Load a realistic CSV dataset directly into the course and let students explore it with SQL queries. This is a natural fit for courses on business data, statistics, or research methods where data arrives as spreadsheet exports.

Introductory data analysis — Combine SQL filtering and aggregation with LiaScript’s quiz blocks for guided, self-paced data exploration exercises.

Lightweight NoSQL-style queries — AlaSQL can query JavaScript arrays and JSON objects as if they were tables. This makes it useful for explaining the conceptual bridge between structured data formats and SQL queries.

Courses without internet dependency — Because AlaSQL is JavaScript-native (no WASM download required), the template starts faster than WASM-based alternatives and works well in low-bandwidth environments.

Technical Facts

Try It

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