public final class JoinOperation extends MapReducePlan
Modifier and Type | Class and Description |
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static class |
JoinOperation.JoinKey
Container for join input values.
|
static class |
JoinOperation.MRContainerGroupingComparator
The grouping of the joined values is based on join key only
|
static class |
JoinOperation.MRContainerJoinPartitioner |
static class |
JoinOperation.MRContainerSortComparator
The sorting of the joined values uses ths join key for major order and tag for minor order
|
Plan.MRContainerKeyComparator
cache, conf, counter_container, counter_key, max_input_files, temporary_paths, value_container
Constructor and Description |
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JoinOperation() |
Modifier and Type | Method and Description |
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static DataSet |
mapReduce2(Tree mx,
Tree my,
Tree combine_fnc,
Tree reduce_fnc,
Tree acc_fnc,
Tree zero,
DataSet X,
DataSet Y,
int num_reduces,
String stop_counter,
boolean orderp)
The MapReduce2 physical operator (a reduce-side join)
|
aggregate, closure, outputRecords, repeat
, binarySource, binarySource, clean, collect, collect, distribute_compiled_arguments, dump, fileCache, functional_argument, generator, generator, get_type, getCache, merge, merge, new_path, parsedSource, parsedSource, print_stream, setCache, size
public static final DataSet mapReduce2(Tree mx, Tree my, Tree combine_fnc, Tree reduce_fnc, Tree acc_fnc, Tree zero, DataSet X, DataSet Y, int num_reduces, String stop_counter, boolean orderp) throws Exception
mx
- left mapper functionmy
- right mapper functioncombine_fnc
- optional in-mapper combiner functionreduce_fnc
- reducer functionacc_fnc
- optional accumulator functionzero
- optional the zero value for the accumulatorX
- left data setY
- right data setnum_reduces
- number of reducersstop_counter
- optional counter used in repeat operationorderp
- does the result need to be ordered?Exception
Copyright © 2013 The Apache Software Foundation. All rights reserved.