Package org.apache.hadoop.hive.ql.ppd

Class Summary
ExprWalkerInfo Context for Expression Walker for determining predicate pushdown candidates It contains a ExprInfo object for each expression that is processed.
ExprWalkerProcFactory Expression factory for predicate pushdown processing.
ExprWalkerProcFactory.ColumnExprProcessor  
ExprWalkerProcFactory.DefaultExprProcessor For constants and null expressions
ExprWalkerProcFactory.FieldExprProcessor  
ExprWalkerProcFactory.GenericFuncExprProcessor If all children are candidates and refer only to one table alias then this expr is a candidate else it is not a candidate but its children could be final candidates
OpProcFactory Operator factory for predicate pushdown processing of operator graph Each operator determines the pushdown predicates by walking the expression tree.
OpProcFactory.DefaultPPD Default processor which just merges its children
OpProcFactory.FilterPPD Determines the push down predicates in its where expression and then combines it with the push down predicates that are passed from its children
OpProcFactory.JoinPPD Determines predicates for which alias can be pushed to it's parents.
OpProcFactory.ReduceSinkPPD Processor for ReduceSink operator.
OpProcFactory.ScriptPPD Processor for Script Operator Prevents any predicates being pushed
OpProcFactory.TableScanPPD Combines predicates of its child into a single expression and adds a filter op as new child
OpWalkerInfo Context class for operator walker of predicate pushdown.
PredicatePushDown Implements predicate pushdown.
 



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