public class Merge extends Splice
The behavior is similar to the GroupBy
merging features, but Merge does not perform any grouping or
sorting on keys. Thus, when using a MapReduce platform, no Reducer is required.
Merge is non-blocking and performs no processing. Any number of branches and merges may be performed in a
Flow
without triggering any additional MapReduce jobs on the Hadoop platform.
Unlike HashJoin
, no preference need be made for left-hand or right-hand sided-ness of streams in relation
to their sizes.
GroupBy
,
Serialized FormdeclaredFields, keyFieldsMap, resultGroupFields, sortFieldsMap
configDef, name, nodeConfigDef, parent, previous, stepConfigDef
Constructor and Description |
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Merge(Pipe... pipes)
Constructor Merge creates a new Merge instance.
|
Merge(java.lang.String name,
Pipe... pipes)
Constructor Merge creates a new Merge instance.
|
equals, getDeclaredFields, getJoinDeclaredFields, getJoiner, getKeySelectors, getName, getNumSelfJoins, getPipePos, getPrevious, getSortingSelectors, hashCode, isCoGroup, isGroupBy, isJoin, isMerge, isSelfJoin, isSorted, isSortReversed, outgoingScopeFor, printInternal, resolveIncomingOperationPassThroughFields, toString
getConfigDef, getHeads, getNodeConfigDef, getParent, getStepConfigDef, getTrace, hasConfigDef, hasNodeConfigDef, hasStepConfigDef, id, named, names, pipes, print, resolveIncomingOperationArgumentFields, setParent
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