1. A computer implemented method for pre-loading an in-memory database into memory of a plurality of compute nodes of a parallel computer system, the method comprising the steps of: receiving a database structure to load into the in-memory database in the plurality of compute nodes; determining an optimized data node mapping to cluster database attributes across multiple compute nodes, wherein clustering database attributes across multiple compute nodes comprises placing data corresponding to a first attribute for a plurality of records together on a first compute node of the computer system and placing data corresponding to a second attribute for the plurality of records together on a second compute node of the computer system; clustering the database attributes based on a use flag in an SQL statement that indicates an anticipated access frequency of placing a record of the plurality of records in the in-memory database; and loading the database structure into the in-memory database with the determined optimized data node mapping.