org.apache.hadoop.hive.ql.optimizer

Class DynamicPartitionPruningOptimization

java.lang.Object

org.apache.hadoop.hive.ql.optimizer.DynamicPartitionPruningOptimization

All Implemented Interfaces:

NodeProcessor

public class DynamicPartitionPruningOptimization
extends Object
implements NodeProcessor

This optimization looks for expressions of the kind "x IN (RS[n])". If such an expression made it to a table scan operator and x is a partition column we can use an existing join to dynamically prune partitions. This class sets up the infrastructure for that.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DynamicPartitionPruningOptimization.DynamicPartitionPrunerProc

Constructor Summary

Constructors

Constructor and Description
DynamicPartitionPruningOptimization()

Method Summary

Methods

Modifier and Type	Method and Description
Object	process(Node nd, Stack<Node> stack, NodeProcessorCtx procCtx, Object... nodeOutputs) Generic process for all ops that don't have specific implementations.

Methods inherited from class java.lang.Object

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

Constructor Detail

DynamicPartitionPruningOptimization

public DynamicPartitionPruningOptimization()

Method Detail

process

public Object process(Node nd,
             Stack<Node> stack,
             NodeProcessorCtx procCtx,
             Object... nodeOutputs)
               throws SemanticException

Description copied from interface: NodeProcessor

Generic process for all ops that don't have specific implementations.

Specified by:

process in interface NodeProcessor

Parameters:

nd - operator to process

procCtx - operator processor context

nodeOutputs - A variable argument list of outputs from other nodes in the walk

Returns:

Object to be returned by the process call

Throws:

SemanticException