QUERY OPTIMIZATION ADAPTIVE TO SYSTEM MEMORY LOAD FOR PARALLEL DATABASE SYSTEMS

摘要

A method for adaptively generating a query execution plan for a parallel database distributed among a cluster of data nodes includes receiving memory usage data from a multiple data nodes including network devices, calculating a representative memory load corresponding to the data nodes based on the memory usage data, categorizing a memory mode corresponding to the data nodes based on the calculated representative memory load, calculating an available work memory corresponding to the data nodes based on the memory mode, and generating the query execution plan for the data nodes based on the available work memory, wherein the memory usage data is based on monitored individual memory loads associated with the data nodes and the query execution plan corresponds to the currently available work memory.