Andrej Pashchenko started his IT career in the early 1990s and has been working with Oracle Database since 1999. Over the past 15 years, he has focused on consulting, supporting customer projects in the areas of data warehousing, data modeling, ETL, and SQL performance. He has been actively sharing his knowledge since 2011 through blogging, speaking at international conferences, and teaching, helping others get the best out of Oracle Database. For his technical expertise and his long-standing commitment to knowledge sharing, Oracle has recognized him as an Oracle ACE Pro.