com.ebay.erl.mobius.core.function
Class UniqueCounts
java.lang.Object
com.ebay.erl.mobius.core.function.base.Projectable
com.ebay.erl.mobius.core.function.base.GroupFunction
com.ebay.erl.mobius.core.function.Unique
com.ebay.erl.mobius.core.function.UniqueCounts
- All Implemented Interfaces:
- java.io.Serializable, org.apache.hadoop.conf.Configurable
public class UniqueCounts
- extends Unique
Computes the number of unique values for the given
inputColumns
in a group.
Uniqueness is measured within the values from
the specified inputColumns
in
UniqueCounts(Column...)
in a group.
This product is licensed under the Apache License, Version 2.0,
available at http://www.apache.org/licenses/LICENSE-2.0.
This product contains portions derived from Apache hadoop which is
licensed under the Apache License, Version 2.0, available at
http://hadoop.apache.org.
© 2007 – 2012 eBay Inc., Evan Chiu, Woody Zhou, Neel Sundaresan
- See Also:
- Serialized Form
Fields inherited from class com.ebay.erl.mobius.core.function.Unique |
temp |
Methods inherited from class com.ebay.erl.mobius.core.function.base.Projectable |
calledByCombiner, equals, getConf, getInputColumns, getOutputSchema, getParticipatedDataset, hashCode, init, isCombinable, requireDataFromMultiDatasets, setCalledByCombiner, setConf, setOutputSchema, setReporter, toString, useGroupKeyOnly |
Methods inherited from class java.lang.Object |
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
UniqueCounts
public UniqueCounts(Column... inputColumns)
- Create an instance of
UniqueCounts
to calculate
number of unique rows within a group.
Uniqueness is measured only within the values
from inputColumns.
getResult
public BigTupleList getResult()
- Override the implementation from
Unique
,
only output single row per group. The row contains
only one column which represents the number of
unique rows in a group.
- Overrides:
getResult
in class Unique