1. A computer data processing system for determining database workload periodicity, the computer data processing system comprising: a converting module for converting database activity samples spanning a time period from the time domain to the frequency domain, said converting module providing a frequency spectrum; an identifying module for identifying fundamental peaks of said frequency spectrum; and an allocating module for allocating database resources based on at least one of said fundamental peaks, wherein: said identifying module for identifying fundamental peaks of said frequency spectrum comprises: a generating module for generating an energy-density spectrum from said frequency spectrum; and an identification module for identifying fundamental peaks of said energy-density spectrum, said identification module for identifying fundamental peaks of said energy-density spectrum comprises: a selecting module for selecting an energy component of said energy-density spectrum, said selected energy component having a highest amplitude of all energy components of said energy-density spectrum; a setting module for setting a threshold based on said amplitude of said selected energy component; and an including module for including within a fundamental peak each adjacent energy component having an amplitude exceeding said threshold, and said computer data processing system further comprises a computing module for computing, for each fundamental peak of said energy-density spectrum, the power of said fundamental peak and any associated harmonics.