Hive多分隔符支持示例

Posted 2021-04-29 Hadoop实操

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1.问题描述

如何将多个字符作为字段分割符的数据文件加载到Hive表中，事例数据如下：

字段分隔符为“@#$”

test1@#$test1name@#$test2value test2@#$test2name@#$test2value test3@#$test3name@#$test4value

如何将上述事例数据加载到Hive表(multi_delimiter_test)中，表结构如下：

字段名	字段类型
s1	String
s2	String
s3	String

2.Hive多分隔符支持

Hive在0.14及以后版本支持字段的多分隔符，参考https://cwiki.apache.org/confluence/display/Hive/MultiDelimitSerDe

3.实现方式

• 测试环境说明

测试环境为CDH5.11.1 Hive版本为1.1.0 操作系统为RedHat6.5

• 操作步骤

1.准备多分隔符文件并装载到HDFS对应目录

[ec2-user@ip-172-31-8-141  ~]$ cat multi_delimiter_test.dat test1@#$test1name@#$test2value test2@#$test2name@#$test2value test3@#$test3name@#$test4value   [ec2-user@ip-172-31-8-141  ~]$ hadoop dfs -put multi_delimiter_test.dat /fayson/multi_delimiter_test [ec2-user@ip-172-31-8-141  ~]$ hadoop dfs -ls /fayson/multi_delimiter_test DEPRECATED: Use of this  script to execute hdfs command is deprecated. Instead use the hdfs  command for it.   Found 1 items -rw-r--r--   3 user_r supergroup         93 2017-08-23 03:24  /fayson/multi_delimiter_test/multi_delimiter_test.dat [ec2-user@ip-172-31-8-141  ~]$

2.基于准备好的多分隔符文件建表

create  external table multi_delimiter_test( s1 string, s2 string, s3 string) ROW FORMAT  SERDE 'org.apache.hadoop.hive.contrib.serde2.MultiDelimitSerDe' WITH  SERDEPROPERTIES ("field.delim"="@#$") stored as  textfile location '/fayson/multi_delimiter_test';

3.测试

2: jdbc:hive2://localhost:10000/default>  select * from multi_delimiter_test; +--------------------------+--------------------------+--------------------------+--+ |  multi_delimiter_test.s1  |  multi_delimiter_test.s2  |  multi_delimiter_test.s3  | +--------------------------+--------------------------+--------------------------+--+ | test1                    | test1name                | test2value               | | test2                    | test2name                | test2value               | | test3                    | test3name                | test4value               | +--------------------------+--------------------------+--------------------------+--+

2:  jdbc:hive2://localhost:10000/default> select count(*) from  multi_delimiter_test;   INFO  : Ended Job = job_1503469952834_0006 INFO  : MapReduce Jobs Launched: INFO  : Stage-Stage-1: Map: 1  Reduce: 1    Cumulative CPU: 3.25 sec   HDFS  Read: 6755 HDFS Write: 2 SUCCESS INFO  : Total MapReduce CPU Time Spent: 3 seconds  250 msec INFO  : Completed executing command(queryId=hive_20170823041818_ce58aae2-e6db-4eed-b6af-652235a6e66a);  Time taken: 33.286 seconds INFO  : OK +------+--+ | _c0  | +------+--+ | 3    | +------+--+ 1 row selected (33.679  seconds) 2:  jdbc:hive2://localhost:10000/def

4.常见问题

1.执行count查询时报错

• 异常日志

通过beeline执行count查询时报错

2:  jdbc:hive2://localhost:10000/default> select count(*) from  multi_delimiter_test; INFO  : Compiling  command(queryId=hive_20170823035959_f1b11a9b-757d-4d9b-b8a7-6d4ab1c00a97):  select count(*) from multi_delimiter_test INFO  : Semantic Analysis Completed INFO  : Returning Hive schema:  Schema(fieldSchemas:[FieldSchema(name:_c0, type:bigint, comment:null)],  properties:null) INFO  : Completed compiling  command(queryId=hive_20170823035959_f1b11a9b-757d-4d9b-b8a7-6d4ab1c00a97);  Time taken: 0.291 seconds INFO  : Executing  command(queryId=hive_20170823035959_f1b11a9b-757d-4d9b-b8a7-6d4ab1c00a97):  select count(*) from multi_delimiter_test INFO  : Query ID =  hive_20170823035959_f1b11a9b-757d-4d9b-b8a7-6d4ab1c00a97 INFO  : Total jobs = 1 INFO  : Launching Job 1 out of 1 INFO  : Starting task [Stage-1:MAPRED] in serial  mode INFO  : Number of reduce tasks determined at  compile time: 1 INFO  : In order to change the average load for a  reducer (in bytes): INFO  :    set hive.exec.reducers.bytes.per.reducer=<number> INFO  : In order to limit the maximum number of  reducers: INFO  :    set hive.exec.reducers.max=<number> INFO  : In order to set a constant number of  reducers: INFO  :    set mapreduce.job.reduces=<number> INFO  : number of splits:1 INFO  : Submitting tokens for job:  job_1503469952834_0002 INFO  : Kind: HDFS_DELEGATION_TOKEN, Service:  ha-hdfs:nameservice1, Ident: (token for hive: HDFS_DELEGATION_TOKEN  owner=hive/[e-mail],  renewer=yarn, realUser=, issueDate=1503475160778, maxDate=1504079960778,  sequenceNumber=27, masterKeyId=9) INFO  : The url to track the job:  http://ip-172-31-9-186.ap-southeast-1.compute.internal:8088/proxy/application_1503469952834_0002/ INFO  : Starting Job = job_1503469952834_0002,  Tracking URL =  http://ip-172-31-9-186.ap-southeast-1.compute.internal:8088/proxy/application_1503469952834_0002/ INFO  : Kill Command =  /opt/cloudera/parcels/CDH-5.10.2-1.cdh5.10.2.p0.5/lib/hadoop/bin/hadoop  job  -kill job_1503469952834_0002 INFO  : Hadoop job information for Stage-1:  number of mappers: 1; number of reducers: 1 INFO  : 2017-08-23 03:59:32,039 Stage-1 map =  0%,  reduce = 0% INFO  : 2017-08-23 04:00:08,106 Stage-1 map =  100%,  reduce = 100% ERROR : Ended Job =  job_1503469952834_0002 with errors ERROR : FAILED: Execution  Error, return code 2 from org.apache.hadoop.hive.ql.exec.mr.MapRedTask INFO  : MapReduce Jobs Launched: INFO  : Stage-Stage-1: Map: 1  Reduce: 1    HDFS Read: 0 HDFS Write: 0 FAIL INFO  : Total MapReduce CPU Time Spent: 0 msec INFO  : Completed executing  command(queryId=hive_20170823035959_f1b11a9b-757d-4d9b-b8a7-6d4ab1c00a97);  Time taken: 48.737 seconds Error: Error while  processing statement: FAILED: Execution Error, return code 2 from  org.apache.hadoop.hive.ql.exec.mr.MapRedTask (state=08S01,code=2)

使用Hive的shell操作报错如下

Error:  java.lang.RuntimeException: Error in configuring object         at  org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:109)         at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:75)         at  org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:133)         at  org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:449)         at org.apache.hadoop.mapred.MapTask.run(MapTask.java:343)         at  org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)         at  java.security.AccessController.doPrivileged(Native Method)         at  javax.security.auth.Subject.doAs(Subject.java:415)         at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1920)         at  org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158) Caused by:  java.lang.reflect.InvocationTargetException         at  sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)         at  sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)         at  sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)         at  java.lang.reflect.Method.invoke(Method.java:606)         at  org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:106)         ... 9 more Caused by:  java.lang.RuntimeException: Error in configuring object         at  org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:109)         at  org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:75)         at  org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:133)         at  org.apache.hadoop.mapred.MapRunner.configure(MapRunner.java:38)         ... 14 more Caused by:  java.lang.reflect.InvocationTargetException         at  sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)         at  sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)         at  sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)         at  java.lang.reflect.Method.invoke(Method.java:606)         at  org.apache.hadoop.util.ReflectionUtils.setJobConf(ReflectionUtils.java:106)         ... 17 more Caused by:  java.lang.RuntimeException: Map operator initialization failed         at  org.apache.hadoop.hive.ql.exec.mr.ExecMapper.configure(ExecMapper.java:147)         ... 22 more Caused by:  org.apache.hadoop.hive.ql.metadata.HiveException:  java.lang.ClassNotFoundException: Class  org.apache.hadoop.hive.contrib.serde2.MultiDelimitSerDe not found         at  org.apache.hadoop.hive.ql.exec.MapOperator.getConvertedOI(MapOperator.java:323)         at  org.apache.hadoop.hive.ql.exec.MapOperator.setChildren(MapOperator.java:333)         at  org.apache.hadoop.hive.ql.exec.mr.ExecMapper.configure(ExecMapper.java:116)         ... 22 more Caused by:  java.lang.ClassNotFoundException: Class  org.apache.hadoop.hive.contrib.serde2.MultiDelimitSerDe not found         at  org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:2105)         at  org.apache.hadoop.hive.ql.plan.PartitionDesc.getDeserializer(PartitionDesc.java:140)         at  org.apache.hadoop.hive.ql.exec.MapOperator.getConvertedOI(MapOperator.java:297)         ... 24 more   FAILED: Execution Error,  return code 2 from org.apache.hadoop.hive.ql.exec.mr.MapRedTask MapReduce Jobs Launched: Stage-Stage-1: Map:  1  Reduce: 1   HDFS Read: 0 HDFS Write: 0 FAIL Total MapReduce CPU Time  Spent: 0 ms

• 问题原因分析

org.apache.hadoop.hive.contrib.serde2.MultiDelimitSerDe类是hive-contrib.jar包里。

在执行非聚合类操作查询时，sql能正常执行，在进行聚合类函数操作时报错，说明在执行MapReduce任务时缺少jar依赖包；MapReduce属于yarn作业，所以yarn运行环境缺少hive-contrib.jar的依赖包。

• 解决方法

在CDH集群的所有节点一下操作，将hive-contrib-1.1.0-cdh5.10.2.jar包拷贝到yarn的lib目录下

sudo scp -r  /opt/cloudera/parcels/CDH/lib/hive/lib/hive-contrib-1.1.0-cdh5.10.2.jar  /opt/cloudera/parcels/CDH/lib/hadoop-yarn/lib/

重新运行count语句，执行成功

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