See: Description
| Class | Description |
|---|---|
| Aggregate |
Methods for performing various types of aggregations over
PCollection instances. |
| Aggregate.PairValueComparator<K,V> | |
| Aggregate.TopKCombineFn<K,V> | |
| Aggregate.TopKFn<K,V> | |
| Average | |
| Cartesian |
Utilities for Cartesian products of two
PTable or PCollection
instances. |
| Channels | |
| Cogroup | |
| Distinct |
Functions for computing the distinct elements of a
PCollection. |
| DoFns | |
| Join |
Utilities for joining multiple
PTable instances based on a common
lastKey. |
| Mapred |
Static functions for working with legacy Mappers and Reducers that live under the org.apache.hadoop.mapred.*
package as part of Crunch pipelines.
|
| Mapreduce |
Static functions for working with legacy Mappers and Reducers that live under the org.apache.hadoop.mapreduce.*
package as part of Crunch pipelines.
|
| PTables |
Methods for performing common operations on PTables.
|
| Quantiles | |
| Quantiles.Result<V> |
Output type for storing the results of a Quantiles computation
|
| Sample |
Methods for performing random sampling in a distributed fashion, either by accepting each
record in a
PCollection with an independent probability in order to sample some
fraction of the overall data set, or by using reservoir sampling in order to pull a uniform
or weighted sample of fixed size from a PCollection of an unknown size. |
| SecondarySort |
Utilities for performing a secondary sort on a
PTable<K, Pair<V1, V2>> collection. |
| Set |
Utilities for performing set operations (difference, intersection, etc) on
PCollection instances. |
| Shard |
Utilities for controlling how the data in a
PCollection is balanced across reducers
and output files. |
| Sort |
Utilities for sorting
PCollection instances. |
| Sort.ColumnOrder |
To sort by column 2 ascending then column 1 descending, you would use:
sortPairs(coll, by(2, ASCENDING), by(1, DESCENDING))
Column numbering is 1-based. |
| TopList |
Tools for creating top lists of items in PTables and PCollections
|
| Enum | Description |
|---|---|
| Sort.Order |
For signaling the order in which a sort should be done.
|
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