描述：

可以建库建表

但无法插入数据

hive> insert into stu1 values(1,"ss");
Query ID = atguigu_20230316212603_bd0f5655-043f-4fe3-93b5-57e2d8782d44
Total jobs = 3
Launching Job 1 out of 3
Number of reduce tasks determined at compile time: 1
In order to change the average load for a reducer (in bytes):
  set hive.exec.reducers.bytes.per.reducer=<number>
In order to limit the maximum number of reducers:
  set hive.exec.reducers.max=<number>
In order to set a constant number of reducers:
  set mapreduce.job.reduces=<number>
Starting Job = job_1678967218927_0006, Tracking URL = http://hadoop103:8088/proxy/application_1678967218927_0006/
Kill Command = /opt/module/hadoop-3.1.3/bin/mapred job  -kill job_1678967218927_0006
Hadoop job information for Stage-1: number of mappers: 0; number of reducers: 0
2023-03-16 21:26:10,910 Stage-1 map = 0%,  reduce = 0%
Ended Job = job_1678967218927_0006 with errors
Error during job, obtaining debugging information...
FAILED: Execution Error, return code 2 from org.apache.hadoop.hive.ql.exec.mr.MapRedTask
MapReduce Jobs Launched: 
Stage-Stage-1:  HDFS Read: 0 HDFS Write: 0 FAIL
Total MapReduce CPU Time Spent: 0 msec

过程

刚开始：Error, return code 2 from org.apache.hadoop.hive.ql.exec.mr.MapRedTask

从网上找这个的报错

https://blog..net/weixin_48874360/article/details/125508644

安照上面的博客改报错，以为是yarn没有配置好，改完后，未解决，于是去看hive日志。

tail -200 /tmp/用户名/hive.log

看到很多error，查完资料后，发现还是不行。

于是从上面的hive命令行的信息找

vim mapred-site.xml

打开这个web后，从history中发现是

Error: Could not find or load main class org.apache.hadoop.mapreduce.v2.app.MRAppMaster

照着这个更改后，发现还是不行。

去网上找资料后发现，还需要添加一下配置信息。

解决

hadoop classpath

将输出的结果复制

vim mapred-site.xml

<property>
        <name>mapreduce.application.classpath</name>
        <value>$HADOOP_MAPRED_HOME/share/hadoop/mapreduce/*:$HADOOP_MAPRED_HOME/share/hadoop/mapreduce/lib/*</value>
    </property>
    <property>
      <name>yarn.app.mapreduce.am.env</name>
      <value>HADOOP_MAPRED_HOME=${HADOOP_HOME}</value>
    </property>
    <property>
      <name>mapreduce.map.env</name>
      <value>HADOOP_MAPRED_HOME=${HADOOP_HOME}</value>
    </property>
    <property>
      <name>mapreduce.reduce.env</name>
      <value>HADOOP_MAPRED_HOME=${HADOOP_HOME}</value>
    </property>

<property>
    <name>yarn.application.classpath</name>
    <value>复制的信息(将其中的:改成,)
    </value>
  </property>