Patent ID: 8849749

Claim:
A method of load balancing in a parallel database system comprising at least a plurality of database nodes, the method comprising: identifying a database node having an excessive load, the excessive load being a load that is greater than loads on other nodes of said plurality of nodes; determining a threshold number of database nodes to which to transfer load from said database node having an excessive load; identifying a group of database nodes having a first subset of database nodes having both at least said threshold number of database nodes and a separate second subset of database nodes such that when an entire load for a first relation is transferred from the first subset of nodes to the second subset of nodes an average load of said second subset of nodes is less than an average load of the plurality of database nodes; and performing a load adjustment comprising transferring said entire load for a first relation from said first subset of database nodes to said second subset of database nodes and transferring load for a second relation from said database node having an excessive load to said first subset of database nodes.