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Pig源码分析: 简析执行计划的生成

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摘要

本文通过跟代码的方式,分析从输入一批Pig-latin到输出物理执行计划(与launcher引擎有关,一般是MR执行计划,也可以是Spark RDD的执行算子)的整体流程。

不会具体涉及AST如何解析、如何使用了Anltr、逻辑执行计划如何映射、逻辑执行计划如何优化、MR执行计划如何切分为MR Job,而是从输入一批Pig DSL到待执行的真正执行计划的关键变化步骤(方法和类)。


执行计划完整解析

入口处书Main类的main函数

/**
 * The Main-Class for the Pig Jar that will provide a shell and setup a classpath appropriate
 * for executing Jar files.  Warning, this method calls System.exit().
 *
 * @param args
 *            -jar can be used to add additional jar files (colon separated). - will start a
 *            shell. -e will execute the rest of the command line as if it was input to the
 *            shell.
 * @throws IOException
 */
public static void main(String args[]) {
    // add win HADOOP_HOME
    // make sure you have "winutils.exe" under /bin
    // if not, download one from https://github.com/srccodes/hadoop-common-2.2.0-bin/tree/master/bin
	
    // entrance for local debug
    // better try: -x spark -e cmds
    System.exit(run(args, null));
}

Main -> GruntParser,这是第一步。

Main首先进行一些参数初始化(启动模式、输入类型判断、初始化类等等),然后借助GruntParser解析输入的pig-latin脚本


grunt.exec()之后的下一个关键步骤是进入GruntParser的解析。


GruntParser里parse()会依赖PigScriptParser.jj文件,具体代码跟不进去,最终生成的是语法树。

在出现Dump操作之后,进入GruntParser的processDump方法。


这步结束之后是完成了语法层面的解析


PigServer-> QueryParserDriver,PigServer的parseQuery方法会进入QueryParserDriver的parse(query)方法,返回逻辑执行计划


QueryParserDriver->LogicalPlanGenerator,生成逻辑执行计划具体依靠的是LogicalPlanGenerator。



截止到这,是生成了逻辑执行计划


PigServer-> HExecutionEngine,接下来是优化逻辑执行计划生成物理执行计划



接下来HExecutionEngine.compile(LogicalPlan, Properties)先优化逻辑执行计划

HExecutionEngine在初始化的时候,会针对不同的情况组合不同的优化策略(disable某些规则)。



这个PlanOptimizer优化的过程在之前 逻辑执行计划优化 的文档里已经有了具体过程了。

 

生成物理执行计划


主要通过LogToPhyTranslcationVisitor内在walk遍历逻辑执行计划节点的时候,

针对不同的Op accept()时触发对应LogToPhyTranslcationVisitor的多态visit(Op)方法,实现逻辑执行计划步骤同物理执行计划步骤的映射。


接下来就是launchPlan,根据配置启动Launcher,如下是启动了SparkLauncher



SparkLauncher里对物理执行计划的每个步骤进行了RDD操作的翻译(直接对应算子),执行后以SparkStats返回,内含OutputInfo信息(包括结果文件地址等信息)。

关于Pig on Spark如何实现SparkLauncher和翻译物理执行计划算子,可以参考我的Github和这篇博文来阅读代码。


另一条路是启动MapReduceLauncher,MRCompiler把物理执行计划翻译成MR执行计划。主要的翻译过程在compile(PO)方法里。


MR执行计划的翻译主要有两步,

首先是MRCompiler.compile(),把物理执行计划翻译到MapReduce执行计划

其次JobControlCompiler.compile(),输入MROperPlan,返回JobControl,这步控制MR Job队列


以上是从输入脚本到输出执行计划的整体流程。比较粗糙,但关键步骤和过程都有。


例子

为了直观起见,我把自己跑的例子贴出来,包括pig-latin,逻辑执行计划,物理执行计划,MR执行计划。


pig-latin

REGISTER D:/tutorial.jar;

raw = LOAD 'D:/github/flare-spork/tutorial/data/excite-small.log' USING PigStorage('\t') AS (user, time, query);

clean1 = FILTER raw BY org.apache.pig.tutorial.NonURLDetector(query);

clean2 = FOREACH clean1 GENERATE user, time, org.apache.pig.tutorial.ToLower(query) as query;

houred = FOREACH clean2 GENERATE user, org.apache.pig.tutorial.ExtractHour(time) as hour, query;

ngramed1 = FOREACH houred GENERATE user, hour, flatten(org.apache.pig.tutorial.NGramGenerator(query)) as ngram;

ngramed2 = DISTINCT ngramed1;

hour_frequency1 = GROUP ngramed2 BY (ngram, hour);

hour_frequency2 = FOREACH hour_frequency1 GENERATE flatten($0), COUNT($1) as count;

uniq_frequency1 = GROUP hour_frequency2 BY group::ngram;

uniq_frequency2 = FOREACH uniq_frequency1 GENERATE flatten($0), flatten(org.apache.pig.tutorial.ScoreGenerator($1));

uniq_frequency3 = FOREACH uniq_frequency2 GENERATE $1 as hour, $0 as ngram, $2 as score, $3 as count, $4 as mean;

filtered_uniq_frequency = FILTER uniq_frequency3 BY score > 2.0;

ordered_uniq_frequency = ORDER filtered_uniq_frequency BY hour, score;

dump ordered_uniq_frequency;

逻辑执行计划

#-----------------------------------------------
# New Logical Plan:
#-----------------------------------------------
ordered_uniq_frequency: (Name: LOSort Schema: hour#22:chararray,ngram#9:chararray,score#23:double,count#24:long,mean#25:double)
|   |
|   hour:(Name: Project Type: chararray Uid: 22 Input: 0 Column: hour)
|   |
|   score:(Name: Project Type: double Uid: 23 Input: 0 Column: score)
|
|---filtered_uniq_frequency: (Name: LOFilter Schema: hour#22:chararray,ngram#9:chararray,score#23:double,count#24:long,mean#25:double)
    |   |
    |   (Name: GreaterThan Type: boolean Uid: 29)
    |   |
    |   |---score:(Name: Project Type: double Uid: 23 Input: 0 Column: score)
    |   |
    |   |---(Name: Constant Type: double Uid: 28)
    |
    |---uniq_frequency3: (Name: LOForEach Schema: hour#22:chararray,ngram#9:chararray,score#23:double,count#24:long,mean#25:double)
        |   |
        |   (Name: LOGenerate[false,false,false,false,false] Schema: hour#22:chararray,ngram#9:chararray,score#23:double,count#24:long,mean#25:double)
        |   |   |
        |   |   org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::hour:(Name: Project Type: chararray Uid: 22 Input: 0 Column: (*))
        |   |   |
        |   |   group:(Name: Project Type: chararray Uid: 9 Input: 1 Column: (*))
        |   |   |
        |   |   org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::score:(Name: Project Type: double Uid: 23 Input: 2 Column: (*))
        |   |   |
        |   |   org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::count:(Name: Project Type: long Uid: 24 Input: 3 Column: (*))
        |   |   |
        |   |   org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::mean:(Name: Project Type: double Uid: 25 Input: 4 Column: (*))
        |   |
        |   |---(Name: LOInnerLoad[1] Schema: org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::hour#22:chararray)
        |   |
        |   |---(Name: LOInnerLoad[0] Schema: group#9:chararray)
        |   |
        |   |---(Name: LOInnerLoad[2] Schema: org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::score#23:double)
        |   |
        |   |---(Name: LOInnerLoad[3] Schema: org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::count#24:long)
        |   |
        |   |---(Name: LOInnerLoad[4] Schema: org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::mean#25:double)
        |
        |---uniq_frequency2: (Name: LOForEach Schema: group#9:chararray,org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::hour#22:chararray,org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::score#23:double,org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::count#24:long,org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::mean#25:double)
            |   |
            |   (Name: LOGenerate[true,true] Schema: group#9:chararray,org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::hour#22:chararray,org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::score#23:double,org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::count#24:long,org.apache.pig.tutorial.scoregenerator_hour_frequency2_27::mean#25:double)
            |   |   |
            |   |   group:(Name: Project Type: chararray Uid: 9 Input: 0 Column: (*))
            |   |   |
            |   |   (Name: UserFunc(org.apache.pig.tutorial.ScoreGenerator) Type: bag Uid: 20)
            |   |   |
            |   |   |---hour_frequency2:(Name: Project Type: bag Uid: 16 Input: 1 Column: (*))
            |   |
            |   |---(Name: LOInnerLoad[0] Schema: group#9:chararray)
            |   |
            |   |---hour_frequency2: (Name: LOInnerLoad[1] Schema: group::ngram#9:chararray,group::hour#6:chararray,count#14:long)
            |
            |---uniq_frequency1: (Name: LOCogroup Schema: group#9:chararray,hour_frequency2#16:bag{#31:tuple(group::ngram#9:chararray,group::hour#6:chararray,count#14:long)})
                |   |
                |   group::ngram:(Name: Project Type: chararray Uid: 9 Input: 0 Column: group::ngram)
                |
                |---hour_frequency2: (Name: LOForEach Schema: group::ngram#9:chararray,group::hour#6:chararray,count#14:long)
                    |   |
                    |   (Name: LOGenerate[true,false] Schema: group::ngram#9:chararray,group::hour#6:chararray,count#14:long)
                    |   |   |
                    |   |   group:(Name: Project Type: tuple Uid: 10 Input: 0 Column: (*))
                    |   |   |
                    |   |   (Name: UserFunc(org.apache.pig.builtin.COUNT) Type: long Uid: 14)
                    |   |   |
                    |   |   |---ngramed2:(Name: Project Type: bag Uid: 11 Input: 1 Column: (*))
                    |   |
                    |   |---(Name: LOInnerLoad[0] Schema: group#10:tuple(ngram#9:chararray,hour#6:chararray))
                    |   |
                    |   |---ngramed2: (Name: LOInnerLoad[1] Schema: user#1:bytearray,hour#6:chararray,ngram#9:chararray)
                    |
                    |---hour_frequency1: (Name: LOCogroup Schema: group#10:tuple(ngram#9:chararray,hour#6:chararray),ngramed2#11:bag{#30:tuple(user#1:bytearray,hour#6:chararray,ngram#9:chararray)})
                        |   |
                        |   ngram:(Name: Project Type: chararray Uid: 9 Input: 0 Column: ngram)
                        |   |
                        |   hour:(Name: Project Type: chararray Uid: 6 Input: 0 Column: hour)
                        |
                        |---ngramed2: (Name: LODistinct Schema: user#1:bytearray,hour#6:chararray,ngram#9:chararray)
                            |
                            |---ngramed1: (Name: LOForEach Schema: user#1:bytearray,hour#6:chararray,ngram#9:chararray)
                                |   |
                                |   (Name: LOGenerate[false,false,true] Schema: user#1:bytearray,hour#6:chararray,ngram#9:chararray)
                                |   |   |
                                |   |   user:(Name: Project Type: bytearray Uid: 1 Input: 0 Column: (*))
                                |   |   |
                                |   |   hour:(Name: Project Type: chararray Uid: 6 Input: 1 Column: (*))
                                |   |   |
                                |   |   (Name: UserFunc(org.apache.pig.tutorial.NGramGenerator) Type: bag Uid: 7)
                                |   |   |
                                |   |   |---query:(Name: Project Type: chararray Uid: 5 Input: 2 Column: (*))
                                |   |
                                |   |---(Name: LOInnerLoad[user] Schema: user#1:bytearray)
                                |   |
                                |   |---(Name: LOInnerLoad[hour] Schema: hour#6:chararray)
                                |   |
                                |   |---(Name: LOInnerLoad[query] Schema: query#5:chararray)
                                |
                                |---houred: (Name: LOForEach Schema: user#1:bytearray,hour#6:chararray,query#5:chararray)
                                    |   |
                                    |   (Name: LOGenerate[false,false,false] Schema: user#1:bytearray,hour#6:chararray,query#5:chararray)
                                    |   |   |
                                    |   |   user:(Name: Project Type: bytearray Uid: 1 Input: 0 Column: (*))
                                    |   |   |
                                    |   |   (Name: UserFunc(org.apache.pig.tutorial.ExtractHour) Type: chararray Uid: 6)
                                    |   |   |
                                    |   |   |---time:(Name: Project Type: bytearray Uid: 2 Input: 1 Column: (*))
                                    |   |   |
                                    |   |   query:(Name: Project Type: chararray Uid: 5 Input: 2 Column: (*))
                                    |   |
                                    |   |---(Name: LOInnerLoad[user] Schema: user#1:bytearray)
                                    |   |
                                    |   |---(Name: LOInnerLoad[time] Schema: time#2:bytearray)
                                    |   |
                                    |   |---(Name: LOInnerLoad[query] Schema: query#5:chararray)
                                    |
                                    |---clean2: (Name: LOForEach Schema: user#1:bytearray,time#2:bytearray,query#5:chararray)
                                        |   |
                                        |   (Name: LOGenerate[false,false,false] Schema: user#1:bytearray,time#2:bytearray,query#5:chararray)
                                        |   |   |
                                        |   |   user:(Name: Project Type: bytearray Uid: 1 Input: 0 Column: (*))
                                        |   |   |
                                        |   |   time:(Name: Project Type: bytearray Uid: 2 Input: 1 Column: (*))
                                        |   |   |
                                        |   |   (Name: UserFunc(org.apache.pig.tutorial.ToLower) Type: chararray Uid: 5)
                                        |   |   |
                                        |   |   |---query:(Name: Project Type: bytearray Uid: 3 Input: 2 Column: (*))
                                        |   |
                                        |   |---(Name: LOInnerLoad[user] Schema: user#1:bytearray)
                                        |   |
                                        |   |---(Name: LOInnerLoad[time] Schema: time#2:bytearray)
                                        |   |
                                        |   |---(Name: LOInnerLoad[query] Schema: query#3:bytearray)
                                        |
                                        |---clean1: (Name: LOFilter Schema: user#1:bytearray,time#2:bytearray,query#3:bytearray)
                                            |   |
   ...


物理执行计划

|
|---ordered_uniq_frequency: POSort[bag]() - scope-70
    |   |
    |   Project[chararray][0] - scope-68
    |   |
    |   Project[double][2] - scope-69
    |
    |---uniq_frequency3: New For Each(false,false,false,false,false)[bag] - scope-67
        |   |
        |   Project[chararray][1] - scope-57
        |   |
        |   Project[chararray][0] - scope-59
        |   |
        |   Project[double][2] - scope-61
        |   |
        |   Project[long][3] - scope-63
        |   |
        |   Project[double][4] - scope-65
        |
        |---filtered_uniq_frequency: Filter[bag] - scope-53
            |   |
            |   Greater Than[boolean] - scope-56
            |   |
            |   |---Project[double][2] - scope-54
            |   |
            |   |---Constant(2.0) - scope-55
            |
            |---uniq_frequency2: New For Each(true,true)[bag] - scope-52
                |   |
                |   Project[chararray][0] - scope-47
                |   |
                |   POUserFunc(org.apache.pig.tutorial.ScoreGenerator)[bag] - scope-50
                |   |
                |   |---Project[bag][1] - scope-49
                |
                |---uniq_frequency1: Package[tuple]{chararray} - scope-44
                    |
                    |---uniq_frequency1: Global Rearrange[tuple] - scope-43
                        |
                        |---uniq_frequency1: Local Rearrange[tuple]{chararray}(false) - scope-45
                            |   |
                            |   Project[chararray][0] - scope-46
                            |
                            |---hour_frequency2: New For Each(true,false)[bag] - scope-42
                                |   |
                                |   Project[tuple][0] - scope-37
                                |   |
                                |   POUserFunc(org.apache.pig.builtin.COUNT)[long] - scope-40
                                |   |
                                |   |---Project[bag][1] - scope-39
                                |
                                |---hour_frequency1: Package[tuple]{tuple} - scope-33
                                    |
                                    |---hour_frequency1: Global Rearrange[tuple] - scope-32
                                        |
                                        |---hour_frequency1: Local Rearrange[tuple]{tuple}(false) - scope-34
                                            |   |
                                            |   Project[chararray][2] - scope-35
                                            |   |
                                            |   Project[chararray][1] - scope-36
                                            |
                                            |---ngramed2: PODistinct[bag] - scope-31
                                                |
                                                |---ngramed1: New For Each(false,false,true)[bag] - scope-30
                                                    |   |
                                                    |   Project[bytearray][0] - scope-23
                                                    |   |
                                                    |   Project[chararray][1] - scope-25
                                                    |   |
                                                    |   POUserFunc(org.apache.pig.tutorial.NGramGenerator)[bag] - scope-28
                                                    |   |
                                                    |   |---Project[chararray][2] - scope-27
                                                    |
                                                    |---houred: New For Each(false,false,false)[bag] - scope-22
                                                        |   |
                                                        |   Project[bytearray][0] - scope-14
                                                        |   |
                                                        |   POUserFunc(org.apache.pig.tutorial.ExtractHour)[chararray] - scope-18
                                                        |   |
                                                        |   |---Cast[chararray] - scope-17
                                                        |       |
                                                        |       |---Project[bytearray][1] - scope-16
                                                        |   |
                                                        |   Project[chararray][2] - scope-20
                                                        |
                                                        |---clean2: New For Each(false,false,false)[bag] - scope-13
                                                            |   |
                                                            |   Project[bytearray][0] - scope-5
                                                            |   |
                                                            |   Project[bytearray][1] - scope-7
                                                            |   |
                                                            |   POUserFunc(org.apache.pig.tutorial.ToLower)[chararray] - scope-11
                                                            |   |
                                                            |   |---Cast[chararray] - scope-10
                                                            |       |
                                                            |       |---Project[bytearray][2] - scope-9
                                                            |
                                                            |---clean1: Filter[bag] - scope-1
                                                                |   |
                                                                |   POUserFunc(org.apache.pig.tutorial.NonURLDetector)[boolean] - scope-4
                                                                |   |
                                                                |   |---Cast[chararray] - scope-3
                                                                |       |
                                                                |       |---Project[bytearray][2] - scope-2
                                                                |
                                                                |---raw: Load(D:/github/flare-spork/tutorial/data/excite-small.log:PigStorage('	')) - scope-0

MR执行计划

# Map Reduce Plan                                  
#--------------------------------------------------
MapReduce node scope-72
Map Plan
Local Rearrange[tuple]{tuple}(true) - scope-74
|   |
|   Project[tuple][*] - scope-73
|
|---ngramed1: New For Each(false,false,true)[bag] - scope-30
    |   |
    |   Project[bytearray][0] - scope-23
    |   |
    |   Project[chararray][1] - scope-25
    |   |
    |   POUserFunc(org.apache.pig.tutorial.NGramGenerator)[bag] - scope-28
    |   |
    |   |---Project[chararray][2] - scope-27
    |
    |---houred: New For Each(false,false,false)[bag] - scope-22
        |   |
        |   Project[bytearray][0] - scope-14
        |   |
        |   POUserFunc(org.apache.pig.tutorial.ExtractHour)[chararray] - scope-18
        |   |
        |   |---Cast[chararray] - scope-17
        |       |
        |       |---Project[bytearray][1] - scope-16
        |   |
        |   Project[chararray][2] - scope-20
        |
        |---clean2: New For Each(false,false,false)[bag] - scope-13
            |   |
            |   Project[bytearray][0] - scope-5
            |   |
            |   Project[bytearray][1] - scope-7
            |   |
            |   POUserFunc(org.apache.pig.tutorial.ToLower)[chararray] - scope-11
            |   |
            |   |---Cast[chararray] - scope-10
            |       |
            |       |---Project[bytearray][2] - scope-9
            |
            |---clean1: Filter[bag] - scope-1
                |   |
                |   POUserFunc(org.apache.pig.tutorial.NonURLDetector)[boolean] - scope-4
                |   |
                |   |---Cast[chararray] - scope-3
                |       |
                |       |---Project[bytearray][2] - scope-2
                |
                |---raw: Load(D:/github/flare-spork/tutorial/data/excite-small.log:PigStorage('	')) - scope-0--------
Reduce Plan
Store(file:/tmp/temp1620254926/tmp-1456742965:org.apache.pig.impl.io.InterStorage) - scope-78
|
|---New For Each(true)[bag] - scope-77
    |   |
    |   Project[tuple][0] - scope-76
    |
    |---Package[tuple]{tuple} - scope-75--------
Global sort: false
----------------

MapReduce node scope-80
Map Plan
hour_frequency1: Local Rearrange[tuple]{tuple}(false) - scope-34
|   |
|   Project[chararray][2] - scope-35
|   |
|   Project[chararray][1] - scope-36
|
|---Load(file:/tmp/temp1620254926/tmp-1456742965:org.apache.pig.impl.io.InterStorage) - scope-79--------
Reduce Plan
Store(file:/tmp/temp1620254926/tmp2077335416:org.apache.pig.impl.io.InterStorage) - scope-81
|
|---hour_frequency2: New For Each(true,false)[bag] - scope-42
    |   |
    |   Project[tuple][0] - scope-37
    |   |
    |   POUserFunc(org.apache.pig.builtin.COUNT)[long] - scope-40
    |   |
    |   |---Project[bag][1] - scope-39
    |
    |---hour_frequency1: Package[tuple]{tuple} - scope-33--------
Global sort: false
----------------

MapReduce node scope-83
Map Plan
uniq_frequency1: Local Rearrange[tuple]{chararray}(false) - scope-45
|   |
|   Project[chararray][0] - scope-46
|
|---Load(file:/tmp/temp1620254926/tmp2077335416:org.apache.pig.impl.io.InterStorage) - scope-82--------
Reduce Plan
Store(file:/tmp/temp1620254926/tmp-26634357:org.apache.pig.impl.io.InterStorage) - scope-84
|
|---uniq_frequency3: New For Each(false,false,false,false,false)[bag] - scope-67
    |   |
    |   Project[chararray][1] - scope-57
    |   |
    |   Project[chararray][0] - scope-59
    |   |
    |   Project[double][2] - scope-61
    |   |
    |   Project[long][3] - scope-63
    |   |
    |   Project[double][4] - scope-65
    |
    |---filtered_uniq_frequency: Filter[bag] - scope-53
        |   |
        |   Greater Than[boolean] - scope-56
        |   |
        |   |---Project[double][2] - scope-54
        |   |
        |   |---Constant(2.0) - scope-55
        |
        |---uniq_frequency2: New For Each(true,true)[bag] - scope-52
            |   |
            |   Project[chararray][0] - scope-47
            |   |
            |   POUserFunc(org.apache.pig.tutorial.ScoreGenerator)[bag] - scope-50
            |   |
            |   |---Project[bag][1] - scope-49
            |
            |---uniq_frequency1: Package[tuple]{chararray} - scope-44--------
Global sort: false
----------------

MapReduce node scope-86
Map Plan
ordered_uniq_frequency: Local Rearrange[tuple]{chararray}(false) - scope-91
|   |
|   Constant(all) - scope-90
|
|---New For Each(false,false)[tuple] - scope-89
    |   |
    |   Project[chararray][0] - scope-87
    |   |
    |   Project[double][2] - scope-88
    |
    |---Load(file:/tmp/temp1620254926/tmp-26634357:org.apache.pig.impl.builtin.RandomSampleLoader('org.apache.pig.impl.io.InterStorage','100')) - scope-85--------
Reduce Plan
Store(file:/tmp/temp1620254926/tmp-586682361:org.apache.pig.impl.io.InterStorage) - scope-101
|
|---New For Each(false)[tuple] - scope-100
    |   |
    |   POUserFunc(org.apache.pig.impl.builtin.FindQuantiles)[tuple] - scope-99
    |   |
    |   |---Project[tuple][*] - scope-98
    |
    |---New For Each(false,false)[tuple] - scope-97
        |   |
        |   Constant(-1) - scope-96
        |   |
        |   ordered_uniq_frequency: POSort[bag]() - scope-70
        |   |   |
        |   |   Project[chararray][0] - scope-94
        |   |   |
        |   |   Project[double][1] - scope-95
        |   |
        |   |---Project[bag][1] - scope-93
        |
        |---Package[tuple]{chararray} - scope-92--------
Global sort: false
----------------

MapReduce node scope-103
Map Plan
ordered_uniq_frequency: Local Rearrange[tuple]{tuple}(false) - scope-104
|   |
|   Project[chararray][0] - scope-68
|   |
|   Project[double][2] - scope-69
|
|---Load(file:/tmp/temp1620254926/tmp-26634357:org.apache.pig.impl.io.InterStorage) - scope-102--------
Reduce Plan
ordered_uniq_frequency: Store(file:/tmp/temp1620254926/tmp-225116343:org.apache.pig.impl.io.InterStorage) - scope-71
|
|---New For Each(true)[tuple] - scope-107
    |   |
    |   Project[bag][1] - scope-106
    |
    |---PackageLite[tuple]{tuple} - scope-105--------
Global sort: true
Quantile file: file:/tmp/temp1620254926/tmp-586682361
----------------



全文完 :)


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