文件/RDBMS -> flume/sqoop -> HDFS -> Hive -> HDFS -> Sqoop -> RDBMS
其中，本文实现了
- 使用 sqoop 从 RDBMS 中读取数据(非Oozie实现，具体错误将在本文最后说明)
- 从 Hive 处理数据存储到 HDFS
- 使用 sqoop 将 HDFS 存储到 RDBMS 中\
1.复制一个 sqoop example，拷贝 hive-site.xml 文件，拷贝 mysql 依赖包到 lib 目录下
2.增加 sqoop-import.sql 文件用以从 RDBMS 读取数据到 Hive 中
--connect
jdbc:mysql://cen-ubuntu:3306/test
--username
root
--password
ubuntu
--table
user
--hive-database
default
--hive-table
import_from_mysql
--hive-import
--hive-overwrite
--delete-target-dir
3.增加 select.sql 用于使用 Hive 处理数据导出到 HDFS 中(注意说明输出分隔符)
insert overwrite directory '/user/cen/oozie-apps/sqoop2hive2sqoop/output/' ROW format delimited fields terminated by ',' select id,name from default.import_from_mysql;
4.增加 sqoop-export.sql 用于使用 sqoop 将 HDFS 文件导入到 RDBMS 中
--connect
jdbc:mysql://cen-ubuntu:3306/test
--username
root
--password
ubuntu
--table
export_from_hdfs
--export-dir
/user/cen/oozie-apps/sqoop2hive2sqoop/output/
--fields-terminated-by
','
5.修改 job.properties 文件
nameNode=hdfs://cen-ubuntu.cenzhongman.com:8020
jobTracker=localhost:8032
queueName=default
oozieAppsRoot=oozie-apps
oozie.use.system.libpath=true
oozie.wf.application.path=${nameNode}/user/cen/${oozieAppsRoot}/sqoop2hive2sqoop/
outputDir=sqoop2hive2sqoop/output
6.修改 workflow.xml 文件
<workflow-app xmlns="uri:oozie:workflow:0.5" name="sqoop2hive2sqoop-wf">
<start to="hive-node"/>
<action name="hive-node">
<hive xmlns="uri:oozie:hive-action:0.5">
<job-tracker>${jobTracker}</job-tracker>
<name-node>${nameNode}</name-node>
<prepare>
<delete path="${nameNode}/user/cen/${oozieAppsRoot}/${outputDir}"/>
</prepare>
<job-xml>${nameNode}/user/cen/${oozieAppsRoot}/sqoop2hive2sqoop/hive-site.xml</job-xml>
<configuration>
<property>
<name>mapred.job.queue.name</name>
<value>${queueName}</value>
</property>
</configuration>
<script>select.sql</script>
</hive>
<ok to="sqoop-export-node"/>
<error to="hive-fail"/>
</action>
<action name="sqoop-export-node">
<sqoop xmlns="uri:oozie:sqoop-action:0.3">
<job-tracker>${jobTracker}</job-tracker>
<name-node>${nameNode}</name-node>
<configuration>
<property>
<name>mapred.job.queue.name</name>
<value>${queueName}</value>
</property>
</configuration>
<command>export --options-file sqoop-export.sql</command>
<file>${nameNode}/user/cen/${oozieAppsRoot}/sqoop2hive2sqoop/sqoop-export.sql#sqoop-export.sql</file>
</sqoop>
<ok to="end"/>
<error to="sqoop-export-fail"/>
</action>
<kill name="hive-fail">
<message>hive failed, error message[${wf:errorMessage(wf:lastErrorNode())}]</message>
</kill>
<kill name="sqoop-export-fail">
<message>Sqoop export failed, error message[${wf:errorMessage(wf:lastErrorNode())}]</message>
</kill>
<end name="end"/>
</workflow-app>
注意事项
- 各个 action 节点的版本号
- 用到文件拷贝，请使用 file 属性
- Hive 的配置文件不能忘记
7.上传文件到 HDFS 上
8.执行 sqoop 从 MySQL 中读取数据到 Hive 中(此处出现错误 could not load org.apache.hadoop.hive.conf.HiveConf.Make sure HIVE_CONF_DIR is set corretly.原因及解决请看 注2 )
bin/sqoop import --options-file /opt/cdh5.3.6/oozie-4.1.0-cdh5.12.0/oozie-apps/sqoop2hive2sqoop/sqoop-import.sql
9.检查 Hive 中是否已经存在数据，并执行 Oozie
export OOZIE_URL=http://cen-ubuntu:11000/oozie/
bin/oozie job --config /opt/cdh5.3.6/oozie-4.1.0-cdh5.12.0/oozie-apps/sqoop2hive2sqoop/job.properties -run
10.检查程序执行 Wordflow 和 MySQL 中的输出结果
注1：使用 Oozie 通过 sqoop import to hive 执行失败(同样的程序，本地执行成功)，但日志无输出，此处贴出完整 wordflow.xml 文件仅供参考
<workflow-app xmlns="uri:oozie:workflow:0.5" name="sqoop2hive2sqoop-wf">
<start to="sqoop-import-node"/>
<action name="sqoop-import-node">
<sqoop xmlns="uri:oozie:sqoop-action:0.3">
<job-tracker>${jobTracker}</job-tracker>
<name-node>${nameNode}</name-node>
<configuration>
<property>
<name>mapred.job.queue.name</name>
<value>${queueName}</value>
</property>
</configuration>
<command>import --options-file sqoop-import.sql</command>
<file>${nameNode}/user/cen/${oozieAppsRoot}/sqoop2hive2sqoop/sqoop-import.sql#sqoop-import.sql</file>
</sqoop>
<ok to="hive-node"/>
<error to="sqoop-import-fail"/>
</action>
<action name="hive-node">
<hive xmlns="uri:oozie:hive-action:0.5">
<job-tracker>${jobTracker}</job-tracker>
<name-node>${nameNode}</name-node>
<prepare>
<delete path="${nameNode}/user/cen/${oozieAppsRoot}/${outputDir}"/>
</prepare>
<job-xml>${nameNode}/user/cen/${oozieAppsRoot}/sqoop2hive2sqoop/hive-site.xml</job-xml>
<configuration>
<property>
<name>mapred.job.queue.name</name>
<value>${queueName}</value>
</property>
</configuration>
<script>select.sql</script>
</hive>
<ok to="sqoop-export-node"/>
<error to="hive-fail"/>
</action>
<action name="sqoop-export-node">
<sqoop xmlns="uri:oozie:sqoop-action:0.3">
<job-tracker>${jobTracker}</job-tracker>
<name-node>${nameNode}</name-node>
<configuration>
<property>
<name>mapred.job.queue.name</name>
<value>${queueName}</value>
</property>
</configuration>
<command>export --options-file sqoop-export.sql</command>
<file>${nameNode}/user/cen/${oozieAppsRoot}/sqoop2hive2sqoop/sqoop-export.sql#sqoop-export.sql</file>
</sqoop>
<ok to="end"/>
<error to="sqoop-export-fail"/>
</action>
<kill name="sqoop-import-fail">
<message>Sqoop import failed, error message[${wf:errorMessage(wf:lastErrorNode())}]</message>
</kill>
<kill name="hive-fail">
<message>hive failed, error message[${wf:errorMessage(wf:lastErrorNode())}]</message>
</kill>
<kill name="sqoop-export-fail">
<message>Sqoop export failed, error message[${wf:errorMessage(wf:lastErrorNode())}]</message>
</kill>
<end name="end"/>
</workflow-app>
原因剖析：错误出现在 sqoop-import-node
- 找不到 hive 配置文件，尝试 (1):如 hive-node 一样增加说明 --> 无效 尝试(2):在 sqoop-import.sql 中增加 --hive-home /opt/xxx/xxx/xxx --> 无效 尝试(3):修改conf/cation-conf/hive.xml --> 并未配置
- 无法从本地的 sqoop 执行 Hive ？ ? 有机会再探索
注2：执行 sqoop 过程出现错误could not load org.apache.hadoop.hive.conf.HiveConf.Make sure HIVE_CONF_DIR is set corretly.
原因：系统使用了变量$HADOOP_CLASSPATH 但本机未定义
-
解决：增加用户环境变量~/.bash_profile
export HADOOP_CLASSPATH=$HADOOP_CLASSPATH:/opt/cdh5.3.6/hive-1.1.0-cdh5.12.0/lib/*