Rick F. van der Lans is an independent consultant, author, and lecturer specializing in database technology, SQL, and data warehousing. He is managing director of R20/Consultancy. He has been a member of the Dutch ISO committee responsible for developing the SQL standard. For the past 20 years, he has taught SQL classes to thousands of attendees. His popular books, including Introduction to SQL and The SQL Guide to Oracle, have been translated into various languages and have sold more than 100,000 copies. Rick is an internationally acclaimed lecturer. Throughout has career, he has lectured in many European countries, South America, USA, and Australia. You can contact Rick via email at sql@r20.nl.