Itzik Ben-gan T-sql Fundamentals Online

"ITzik Ben-Gan T-SQL Fundamentals" is an excellent resource for anyone looking to learn or refresh their understanding of T-SQL. With its clear explanations, practical examples, and emphasis on best practices, this book provides a solid foundation for working with T-SQL and SQL Server. While it assumes basic SQL knowledge and focuses on SQL Server, it remains an invaluable resource for database professionals and developers.