1. A data-intensive computer comprising: a processing sub-system formed by a plurality of processing servers; a database sub-system formed by a plurality of database servers configured to form a collective database; a unifying operating system environment extending across the processing sub-system and the database sub-system to coordinate operation of the plurality of processing servers and the plurality of database servers to act as components in a single data-intensive computer; and wherein the unifying operating system environment is further configured to present the database sub-system to an application running in the data-intensive computer as a layer in a memory hierarchy of the data-intensive computer.