New concepts for parallel object relational query processing During the last few years parallel object relational database management systems have emerged as the leading data management technology on the market. These systems are extensible by user defined data types and user defined functionality for the data. This work focuses on the efficient parallel execution of user defined functionality. The main contributions describe techniques to support data parallelism for user defined scalar and aggregate functions and intra function parallelism for the execution of a scalar function on a large object and a new technology to provide extensibility with regard to new set oriented database operations that can efficiently implement user defined functionality in parallel object relational database management systems