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

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

All Implemented Interfaces:

PhysicalPlanResolver

public class MapJoinResolver
extends Object
implements PhysicalPlanResolver

An implementation of PhysicalPlanResolver. It iterator each MapRedTask to see whether the task has a local map work if it has, it will move the local work to a new local map join task. Then it will make this new generated task depends on current task's parent task and make current task depends on this new generated task.

Nested Class Summary

static class

MapJoinResolver.LocalMapJoinProcCtx A container of current task and parse context.

Constructor Summary

MapJoinResolver()

Method Summary

PhysicalContext

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

Methods inherited from class java.lang.Object

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

Constructor Detail

MapJoinResolver

public MapJoinResolver()

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