1. A system for managing a plurality of database systems, comprising: (a) one or more computers; (b) a domain comprised of a plurality of database systems executed by the one or more computers, wherein each of the plurality of database systems performs database queries to retrieve data stored by the plurality of database systems; and (c) a plurality of closed-loop system management (CLSM) regulators for managing the database systems wherein: (i) the plurality of CLSM regulators are organized in a tree structure, such that each CLSM regulator aggregates information related to its own database system as well as that of its children CLSM regulators, and reports the aggregated information to its parent CLSM regulator in the tree structure; (ii) at least one of the plurality of CLSM regulators comprises a virtual regulator at a highest level of the tree structure for managing the domain by controlling the CLSM regulators managing the database systems within the domain, and communicating with the CLSM regulators managing the database systems in the domain to compile the aggregated information reported by the CLSM regulators; (iii) each of the plurality of CLSM regulators dynamically monitor a data temperature comprising a frequency of access to the data stored by a specific database system; (iv) each of the plurality of CLSM regulators separate incoming queries into one or more workload groups; (v) each of the one or more workload groups is assigned to one or more respective service level goals (SLGs) that are each comprised of one or more levels of service expected from the plurality of database systems in processing the incoming queries assigned to the respective workload group; (vi) each of the plurality of CLSM regulators dynamically determine a priority class for each workload group based on the respective service level goals; (vii) a workload query manager within each of the plurality CLSM regulators is responsive to workload rules and an exception monitor for either passing on the incoming query or placing the incoming query into a queue until predetermined conditions are met, wherein once passed, the incoming query is placed into its determined priority class; (viii) a priority scheduler facility (PSF) within each of the plurality of the CLSM regulators is responsive to the priority classes, and reports observed system conditions and throughput information to one or more monitors; (ix) the one or more monitors update principles under which the PSF operates based on the observed system conditions and the throughput information, received from the PSF, such that the priority class influences and is used to define the data temperature; and (x) each of the plurality of the CLSM regulators dynamically utilize the priority in conjunction with the data temperature to dynamically allocate resources for the database systems for processing the one or more workload groups.