from:http://blog.csdn.net/haoni123321/article/details/34144027

Streaming支援多路輸出(SuffixMultipleTextOutputFormat)

如下示例:

hadoop streaming \

-input /home/mr/data/test_tab/ \

-output /home/mr/output/tab_test/out19 \

-outputformatorg.apache.hadoop.mapred.lib.SuffixMultipleTextOutputFormat\   # 指定outputformat為org.apache.hadoop.mapred.lib.SuffixMultipleTextOutputFormat

-jobconf suffix.multiple.outputformat.filesuffix=a,c,f,abc,cde  \            # 指定輸出檔名的字首，所有需要輸出的檔名必須通過該引數配置，否則job會失敗

-jobconf suffix.multiple.outputformat.separator="#"\                        # 設定value與檔名的分割符，預設為“#”，如果value本身含有“#”，則可以通過該引數設定其他的分隔符

-mapper "cat" \

-reducer "sh reduce.sh" \

-file reduce.sh

注：標記為紅色的引數必須設定，引數說明請見註釋

Map或者reduce裡需要在每個記錄的reduce追加“#+檔名”

#!/bin/bash 

while read line

do

    key=$(echo $line | awk -F' ' '{print $1}')

    value=$(echo $line | awk -F' ' '{print $2}')

    if [ "$key" == "a" ]

    then

        echo"$key       $value#a"

    fi 

    if [ "$key" == "c" ]

        then

           echo "$key    $value#c"

       fi 

       if [ "$key" =="f" ] 

       then

           echo "$key    $value#f"

       fi

       if [ "$key" =="abc" ]

       then

           echo "$key    $value#abc"

       fi

       if [ "$key" =="cde" ]

       then

           echo "$key    $value#cde"

       fi

done