Abstract: Providing cost model data for tuning query cache memory size in database systems. In one aspect, a query is received, and a query cache is checked to determine whether a stored query matches the received query. When a cache miss has occurred due to no stored queries matching the received query, the processing time saved by the avoidance of the cache miss and a cache size needed to avoid the cache miss are determined.

Abstract: A method and system for caching dynamic SQL statements and their sections at different nodes in a multiple node Relational Database Management System (RDBMS) while maintaining cache and application integrity across all nodes. Each node in the RDBMS having a global cache shared by all applications on that node. One of the nodes in the RDBMS being a catalogue node which controls access to a database. The catalogue node maintaining a list of participating nodes that have requested access to the database controlled by the catalogue node. The list of participating nodes being used to notify each participating node of any changes to the database that may affect the validity of a dynamic SQL statement stored in the global cache of the node.