SQL Documentation (From the Khan Academy)

SQL development

If you're new to SQL, you can learn more from this course: SQL.

Creating tables

• CREATE TABLE customers (id INTEGER PRIMARY KEY, name TEXT, age INTEGER, weight REAL);

  Many data types
• CREATE TABLE customers (id INTEGER PRIMARY KEY, age INTEGER);

  Using primary keys

See also: specifying defaults, using foreign keys. For more details, see the following: SQLite reference for CREATE.

Inserting data

• INSERT INTO customers VALUES (73, "Brian", 33);

  Inserting data
• INSERT INTO customers (name, age) VALUES ("Brian", 33);

  Inserting data for named columns

See also: The SQLite reference for INSERT.

Querying data

• SELECT * FROM customers;

  Select everything
• SELECT * FROM customers WHERE age > 21;

  Filter with condition
• SELECT * FROM customers WHERE age < 21 AND state = "NY";

  Filter with multiple conditions
• SELECT * FROM customers WHERE plan IN ("free", "basic");

  Filter with IN
• SELECT name, age FROM customers;

  Select specific columns
• SELECT * FROM customers WHERE age > 21 ORDER BY age DESC;

  Order results
• SELECT name, CASE WHEN age > 18 THEN "adult" ELSE "minor" END "type" FROM customers;

  Transform with CASE

See also: filtering with LIKE, restricting with LIMIT, using ROUND and other core functions. For more details, see: the SQLite reference for SELECT.

Aggregating data

• SELECT MAX(age) FROM customers;

  Aggregate functions
• SELECT gender, COUNT(*) FROM students GROUP BY gender;

  Grouping data

See also: restricting results with HAVING.

Joining related tables

• SELECT customers.name, orders.item FROM customers JOIN orders ON customers.id = orders.customer_id;

  Inner join
• SELECT customers.name, orders.item FROM customers LEFT OUTER JOIN orders ON customers.id = orders.customer_id;

  Outer join

Updating and deleting data

• UPDATE customers SET age = 33 WHERE id = 73;

  Updating data
• DELETE FROM customers WHERE id = 73;

  Deleting data

Also see: ALTER TABLE.

Our implementation of SQL is based on a popular dialect of SQL known as SQLite.
To run SQL in the browser, we make use of these technologies:

• asm.js
• Emscripten
• sql.js