@MarkusWindand: Thank you for the Websites [1],[2],[3] and the book »SQL Performance Explained«[4]. [1] https://modern-sql.com/ https://modern-sql.com/ [2] ht

@MarkusWindand: Thank you for the Websites [1],[2],[3] and the book »SQL Performance Explained«[4]. [1] https://modern-sql.com/ https://modern-sql.com/ [2] https://use-the-index-luke.com/ https://use-the-index-luke.com/ [3] https://db-engines.com/ https://db-engines.com/ [4] https://www.amazon.de/SQL-Performance-Explained-Everything-performance/dp/3950307826/ https://www.amazon.de/SQL-Performance-Explained-Everything-p...