Tomaž Kastrun is BI & DEV developer, data analyst & data science. With more than 15 years of experiences in the field of databases, business warehouses and development, with a focus on T-SQL programming and query optimization. His focus is also data mining, statistics and research. He has been working with Microsoft SQL Server since version 2000. He is Microsoft MVP, Microsoft Certified Professional and Microsoft Trainer. Tomaž is a blogger, author of many articles, speaker at various community and Microsoft events and an avid coffee drinker. This talk has taken place after SQL Saturday 2019 in Ljubljana, Slovenia on 14 December 2019 (Saturday). Interviewer: Kamil Nowinski (T).