What is SQL?

SQL (Structured Query Language) is how you ask questions of a database. Data lives in tables, which are grids of rows (records) and columns (fields).

Every example on this site runs on a small practice database built into your browser. It has three tables: customers, products and orders. Nothing is sent anywhere, and the database is rebuilt on every Run, so you cannot break it. Press Run:

Examplesql

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SELECT * means "give me every column", and FROM customers says which table. The semicolon ends the statement.

Quick check

What does a row in a table represent?

A field nameOne record, such as one customerA whole database

Your turn: write the code

Select just the name column from the products table.

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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