SQL Reference will help you to understand the basics of SQL and become familiar with the advanced level. Content of the handbook is divided into four categories:
Articles contain syntax (which is highlighted) examples for functions. The description of each function includes some examples with comments.
Reference is also shows major differences of the syntax of the various databases: MySQL, SQL Server, Oracle, Access, SQLite.
Training section allows you to practice in running sql queries. This section availible only in full version.
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