org.apache.hadoop.hive.ql.optimizer
Interface Transform

All Known Implementing Classes:

AnnotateWithOpTraits, AnnotateWithStatistics, BucketingSortingReduceSinkOptimizer, BucketMapJoinOptimizer, ColumnPruner, CorrelationOptimizer, Generator, GlobalLimitOptimizer, GroupByOptimizer, JoinReorder, LimitPushdownOptimizer, ListBucketingPruner, MapJoinProcessor, NonBlockingOpDeDupProc, PartitionConditionRemover, PartitionPruner, PredicatePushDown, PredicateTransitivePropagate, ReduceSinkDeDuplication, RewriteGBUsingIndex, SamplePruner, SimpleFetchAggregation, SimpleFetchOptimizer, SkewJoinOptimizer, SortedDynPartitionOptimizer, SortedMergeBucketMapJoinOptimizer, StatsOptimizer, UnionProcessor

public interface Transform

Optimizer interface. All the rule-based optimizations implement this interface. All the transformations are invoked sequentially. They take the current parse context (which contains the operator tree among other things), perform all the optimizations, and then return the updated parse context.

Method Summary

ParseContext

transform(ParseContext pctx) All transformation steps implement this interface.

Method Detail

transform

ParseContext transform(ParseContext pctx)
                       throws SemanticException

All transformation steps implement this interface.

Parameters:

pctx - input parse context

Returns:

ParseContext

Throws:

SemanticException