SQLBolt — Learn SQL with simple, interactive exercises

Every lesson runs a database in the browser, so you can write your first query without installing anything.

SQL lets both technical and non-technical users query, manipulate, and transform data from a relational database. SQLBolt teaches the common standard shared by SQLite, MySQL, Postgres, Oracle and Microsoft SQL Server.

Most people come to SQL to work with a database that already exists, so the lessons start with the parts of a query. Later ones cover altering a table or schema and creating tables from scratch. Each lesson introduces one concept and ends with an exercise.

Table of contents:
• Lessons 1–4 — SELECT queries 101, queries with constraints, filtering and sorting query results
• Lessons 6–8 — multi-table queries with JOINs, OUTER JOINs, a short note on NULLs
• Lessons 9–12 — queries with expressions, queries with aggregates, order of execution of a query
• Lessons 13–15 — inserting, updating and deleting rows
• Lessons 16–18 — creating, altering and dropping tables

Free, and no account required.

Link: Site

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