Basic Steps in Query Processing 1.Parsing and translation 2.Optimization 3.Evaluation parser and relational-algebra query translator expression optimizer query output evaluation engine execution plan data statistics about data Database System Concepts-6th Edition 12.3 ©Silberschat乜，Korth and SudarshanDatabase System Concepts - 6 12.3 ©Silberschatz, Korth and Sudarshan th Edition Basic Steps in Query Processing 1. Parsing and translation 2. Optimization 3. Evaluation