datafu.pig.util

Class SelectStringFieldByName

java.lang.Object

org.apache.pig.EvalFunc<java.lang.String>

datafu.pig.util.SelectStringFieldByName

public class SelectStringFieldByName
extends org.apache.pig.EvalFunc<java.lang.String>

Selects the value for a field within a tuple using that field's name.

Example:

 
 define SelectStringFieldByName datafu.pig.util.SelectStringFieldByName();

 -- input:
 -- ("text1", "hi", "how", "are")
 input = LOAD 'input' AS (fieldName:chararray, text1:chararray, text2:chararray, text3:chararray);

 -- output:
 -- ("hi")
 outfoo = FOREACH input GENERATE SelectStringFieldByName(fieldName, *) as value;
 
 

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
SelectStringFieldByName()

Method Summary

Modifier and Type	Method and Description
java.lang.String	exec(org.apache.pig.data.Tuple input)

Methods inherited from class org.apache.pig.EvalFunc

allowCompileTimeCalculation, finish, getArgToFuncMapping, getCacheFiles, getInputSchema, getLogger, getPigLogger, getReporter, getReturnType, getSchemaName, getSchemaType, getShipFiles, isAsynchronous, outputSchema, 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

SelectStringFieldByName

public SelectStringFieldByName()

Method Detail

exec

public java.lang.String exec(org.apache.pig.data.Tuple input)
                      throws java.io.IOException

Specified by:

exec in class org.apache.pig.EvalFunc<java.lang.String>

Throws:

java.io.IOException