Database theory and an online tutorial interface to an Oracle database system, allowing a user to learn SQL interactively. The site automatically checks and marks SQL and gives instant feedback.

Introduction to SQL

Interactive/On-line SQL Tutorial with SQL Interpreter and live practice database.

Online SQL tutorial featuring a live interpreter to test SQL commands.

Help everyone to gain or improve skills in building SQL Data Manipulation Language statements. A rating system is supported for SELECT exercises and certification. SQL handbook. English and Russian versions.

Tips on how to troubleshoot SQL queries.

Examples of how to use SQL commands

This article provides a brief SQL How-to on how to summarize data. Most of the examples we provide will be based on the ANSI-SQL 92 standard. Some examples will show features specific to SQL Server 7.

Provides ANSI-SQL solutions to common database query/update tasks. These apply to such relational databases as PostGreSQL, MySQL, Microsoft SQL Server, Oracle, Microsoft Access, SQLite.

Physical Data Model Patterns.