org.apache.hadoop.hive.ql.optimizer.physical
Class BucketingSortingInferenceOptimizer

java.lang.Object
  org.apache.hadoop.hive.ql.optimizer.physical.BucketingSortingInferenceOptimizer

All Implemented Interfaces:

PhysicalPlanResolver

public class BucketingSortingInferenceOptimizer
extends Object
implements PhysicalPlanResolver

BucketingSortingInferenceOptimizer. For each map reduce task, attmepts to infer bucketing and sorting metadata for the outputs. Currently only map reduce tasks which produce final output have there output metadata inferred, but it can be extended to intermediate tasks as well. This should be run as the last physical optimizer, as other physical optimizers may invalidate the inferences made. If a physical optimizer depends on the results and is designed to carefully maintain these inferences, it may follow this one.

Constructor Summary

BucketingSortingInferenceOptimizer()

Method Summary

PhysicalContext

resolve(PhysicalContext pctx) All physical plan resolvers have to implement this entry method.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BucketingSortingInferenceOptimizer

public BucketingSortingInferenceOptimizer()

Method Detail

resolve

public PhysicalContext resolve(PhysicalContext pctx)
                        throws SemanticException

Description copied from interface: PhysicalPlanResolver

All physical plan resolvers have to implement this entry method.

Specified by:

resolve in interface PhysicalPlanResolver

Returns:

the physical plan

Throws:

SemanticException