1. In a shared disk cluster database system comprising a plurality of database server nodes sharing access to a single database, a method for temporarily storing data objects in memory of said shared disk cluster database system, the method comprising: in a shared disk cluster database system comprising a plurality of database server nodes connected via high speed private interconnects and sharing access to a single database, reserving a portion of memory at each of said plurality of database server nodes as a default data cache for temporarily storing data objects; in response to user input, allocating a portion of memory of at least one of said plurality of database server nodes as a named cache reserved for temporarily storing a specified type of data object; maintaining cache binding information in an in-memory mapping structure at each database server node of the shared disk cluster; in response to an operation at a particular database server node requesting a data object, determining whether the requested data object is of the specified type corresponding to the named cache at the particular database server node based on consulting cache binding information at the particular database server node; if the data object is determined to be of the specified type corresponding to the named cache at the particular database server node, temporarily storing the requested data object in the named cache at the particular database server node; and otherwise, using the default data cache at the particular database server node for temporarily storing the requested data object.