1. Database accelerator apparatus, for use in a network having a set of at least one client system each running an application which makes SQL database queries via a network to a particular IP address and port combination, and a set of at least one database server each having access to at least a portion of a database, the accelerator apparatus being arranged to: receive, through a network port, an SQL database query made by the set of client systems and directed to the particular IP address and port combination, the SQL database query including query text; determine, by reference to data objects describing a plurality of pre-existing connections from the accelerator apparatus to the database servers, whether one of the connections is available for the SQL query, and if so, then forward the SQL query through the available connection toward the set of database servers, wherein the data objects are allocated among a plurality of connection pools, wherein the apparatus is further arranged to select a preferred one and a less-preferred one of the connection pools in dependence upon predetermined characteristics of the received database query text, and wherein the determination of whether one of the connections is available for the query consists of a determination of whether a connection in the preferred pool is available for the query, and if not then whether a connection in the less-preferred pool is available for the query.