Database processing using columns to present to a processing unit decompressed column data without changing the underlying row-based database architecture. For some embodiments, a database accelerator is used to efficiently process the columns of a database and output tuples to a processing unit's memory, such that the columns can be quickly processed (with the advantages of a column-based architecture) to create tuples of requested data, but without having to depart from a row-based architecture at the processing unit level or having decompressed data scattered throughout the processing unit's memory.