1. A method for operating a parallel database server system, said database server system comprising at least two database servers and one data source, said method comprising: receiving a client identifier from a first client requesting first services from said database servers, wherein the first services require access to a first data set in the data source, and wherein the first data set of data source is accessible to each of said database servers; retrieving information associated with said first client; selecting a first database server of said at least two database servers based at least in part on the retrieved information and on the first data set required for the first services; receiving a client identifier from a second client requesting second services from said database servers, wherein the second services require access to the first data set in the data source; and allocating both the first client and the second client to the first database server of said database servers, based at least in part on the first services requested by the first client and the second services requested by the second client both requiring access to the first data set, wherein the first database is configured to manage contentions between the first client and the second client on the first data set of the data source.