One or more assignments (e.g., one or more maps) can be used for assigning data to processing units of a database system with multiple processing. In other words, assignments can be provided as a more effective solution for assigning data to the processing units of database systems that can operate with multiple processing units. Generally, an assignment can be used to assign data to the processing units for processing, virtually in any desired manner (e.g., virtually any desired function). By way of example, maps can associate data to containers (e.g., buckets) and associate the containers to processing units of database system with multiple processing units.