datafu.pig.bags

Class BagSplit

java.lang.Object

org.apache.pig.EvalFunc<org.apache.pig.data.DataBag>

datafu.pig.bags.BagSplit

public class BagSplit
extends org.apache.pig.EvalFunc<org.apache.pig.data.DataBag>

Splits a bag of tuples into a bag of bags, where the inner bags collectively contain the tuples from the original bag. This can be used to split a bag into a set of smaller bags.

Example:

 define BagSplit datafu.pig.bags.BagSplit();
 
 -- input:
 -- ({(1),(2),(3),(4),(5),(6),(7)})
 -- ({(1),(2),(3),(4),(5)})
 -- ({(1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11)})
 input = LOAD 'input' AS (B:bag{T:tuple(val1:INT,val2:INT)});
 
 -- ouput:
 -- ({{(1),(2),(3),(4),(5)},{(6),(7)}})
 -- ({{(1),(2),(3),(4),(5)},{(6),(7),(8),(9),(10)},{(11)}})
 output = FOREACH input GENERATE BagSplit(5,B);
 
 

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.pig.EvalFunc

org.apache.pig.EvalFunc.SchemaType

Field Summary

Fields inherited from class org.apache.pig.EvalFunc

log, pigLogger, reporter, returnType

Constructor Summary

Constructors

Constructor and Description
BagSplit()
BagSplit(java.lang.String appendBagNum)

Method Summary

Methods

Modifier and Type	Method and Description
org.apache.pig.data.DataBag	exec(org.apache.pig.data.Tuple arg0)
org.apache.pig.impl.logicalLayer.schema.Schema	outputSchema(org.apache.pig.impl.logicalLayer.schema.Schema input)

Methods inherited from class org.apache.pig.EvalFunc

allowCompileTimeCalculation, finish, getArgToFuncMapping, getCacheFiles, getInputSchema, getLogger, getPigLogger, getReporter, getReturnType, getSchemaName, getSchemaType, getShipFiles, isAsynchronous, progress, setInputSchema, setPigLogger, setReporter, setUDFContextSignature, warn

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BagSplit

public BagSplit()

BagSplit

public BagSplit(java.lang.String appendBagNum)

Method Detail

exec

public org.apache.pig.data.DataBag exec(org.apache.pig.data.Tuple arg0)
                                 throws java.io.IOException

Specified by:

exec in class org.apache.pig.EvalFunc<org.apache.pig.data.DataBag>

Throws:

java.io.IOException

outputSchema

public org.apache.pig.impl.logicalLayer.schema.Schema outputSchema(org.apache.pig.impl.logicalLayer.schema.Schema input)

Overrides:

outputSchema in class org.apache.pig.EvalFunc<org.apache.pig.data.DataBag>