As Data Engineer Database Performance, Efficiency should be among your priorities, and to optimize those you need to understand what influences query Performance and what you can do about it. In this presentation we will look into all the factors which influence query performance - the database engine, data structures and algorithms it uses, query optimizer, various types of indexes and other data access optimization methods as well as hardware innovations which allow us to reach modern performance. After attending this talk you will be better empowered to take the optimal choices to help your team to get the best performance while minimizing your costs.