sqoop2:从mysql导出数据到hdfs

xiaoxiao2026-05-19 12

sqoop2:从mysql导出数据到hdfs中

sqoop－shell

启动sqoopp-shell

jjzhu:bin didi$ sqoop2-shell Setting conf dir: /opt/sqoop-1.99.7/bin/../conf Sqoop home directory: /opt/sqoop-1.99.7 Sqoop Shell: Type 'help' or '\h' for help. sqoop:000> set server --host localhost --port 12000 --webapp sqoop Server is set successfully sqoop:000> show version --all client version: Sqoop 1.99.7 source revision 435d5e61b922a32d7bce567fe5fb1a9c0d9b1bbb Compiled by abefine on Tue Jul 19 16:08:27 PDT 2016 0 [main] WARN org.apache.hadoop.util.NativeCodeLoader - Unable to load native-hadoop library for your platform... using builtin-java classes where applicable server version: Sqoop 1.99.7 source revision 435d5e61b922a32d7bce567fe5fb1a9c0d9b1bbb Compiled by abefine on Tue Jul 19 16:08:27 PDT 2016 API versions: [v1] sqoop:000>

配置sqoop server

sqoop:000> set server --host localhost --port 12000 --webapp sqoop Server is set successfully

查看server连接是否可用

sqoop:000> show version --all client version: Sqoop 1.99.7 source revision 435d5e61b922a32d7bce567fe5fb1a9c0d9b1bbb Compiled by abefine on Tue Jul 19 16:08:27 PDT 2016 0 [main] WARN org.apache.hadoop.util.NativeCodeLoader - Unable to load native-hadoop library for your platform... using builtin-java classes where applicable server version: Sqoop 1.99.7 source revision 435d5e61b922a32d7bce567fe5fb1a9c0d9b1bbb Compiled by abefine on Tue Jul 19 16:08:27 PDT 2016 API versions: [v1] sqoop:000>

创建链接

查看sqoop server上可用的链接

用如下命令创建一个generic-jdbc-connector的链接

sqoop:002> create link -c generic-jdbc-connector Creating link for connector with name generic-jdbc-connector Please fill following values to create new link object Name: mysql_weibouser_link Database connection Driver class: com.mysql.jdbc.Driver Connection String: jdbc:mysql://127.0.0.1:3306/spider Username: root Password: **** Fetch Size: Connection Properties: There are currently 0 values in the map: entry# protocol=tcp There are currently 1 values in the map: protocol = tcp entry# SQL Dialect Identifier enclose: **注意这里不能直接回车！要打一个空格符号！因为如果不打，查询mysql表的时候会在表上加上“”，导致查询出错！ ** New link was successfully created with validation status OK and name mysql_weibouser_link

创建hdfs link

sqoop:002> create link -c hdfs-connector Creating link for connector with name hdfs-connector Please fill following values to create new link object Name: hdfs_weibouser_link HDFS cluster URI: hdfs://localhost:9000 Conf directory: /opt/hadoop-2.7.3/etc/hadoop Additional configs:: There are currently 0 values in the map: entry# New link was successfully created with validation status OK and name hdfs_weibouser_link

查看link

创建job

sqoop:002> create job -f "mysql_weibouser_link" -t "hdfs_weibouser_link" Creating job for links with from name mysql_weibouser_link and to name hdfs_weibouser_link Please fill following values to create new job object Name: job_weibouser Database source Schema name: spider Table name: spiders_weibouser SQL statement: Column names: There are currently 0 values in the list: element# Partition column: Partition column nullable: Boundary query: Incremental read Check column: Last value: Target configuration Override null value: Null value: File format: 0 : TEXT_FILE 1 : SEQUENCE_FILE 2 : PARQUET_FILE Choose: 0 Compression codec: 0 : NONE 1 : DEFAULT 2 : DEFLATE 3 : GZIP 4 : BZIP2 5 : LZO 6 : LZ4 7 : SNAPPY 8 : CUSTOM Choose: 0 Custom codec: Output directory: hdfs://localhost:9000/usr/jjzhu/spider/spiders_weibouser Append mode: Throttling resources Extractors: 2 Loaders: 2 Classpath configuration Extra mapper jars: There are currently 0 values in the list: element# New job was successfully created with validation status OK and name job_weibouser

各参数意义：

以下是各个属性 Name：一个标示符，自己指定即可。 Schema Name：指定Database或Schema的名字，在MySQL中，Schema同Database类似，具体什么区别没有深究过，但官网描述在创建时差不多。。 Table Name：自己指定导出的表。 SQL Statement：就是sql查询语句，文档上说需要指定一个$condition，但我一直没有创建成功，貌似是一个条件子句。配置完以上几项，又回出现element#提示符，提示输入一些hash值，直接回车过。 Partition column: Partition column nullable: Boundary query Last value 后面需要配置数据目的地各项值： Null alue：大概说的是如果有空值用什么覆盖 File format：指定在HDFS中的数据文件是什么文件格式，这里使用TEXT_FILE，即最简单的文本文件。 Compression codec：用于指定使用什么压缩算法进行导出数据文件压缩，我指定NONE，这个也可以使用自定义的压缩算法CUSTOM，用Java实现相应的接口。 Custom codec：这个就是指定的custom压缩算法，本例选择NONE，所以直接回车过去。 Output directory：指定存储在HDFS文件系统中的路径，这里最好指定一个存在的路径，或者存在但路劲下是空的，貌似这样才能成功。 Append mode：用于指定是否是在已存在导出文件的情况下将新数据追加到数据文件中。 Extractors：2 Loaders：2 最后再次出现element#提示符，用于输入extra mapper jars的属性，可以什么都不写。直接回车。至此若出现successful则证明已经成功创建。

查看创建的job

启动job

start job -n job_weibouser sqoop:002> start job -n job_weibouser Submission details Job Name: job_weibouser Server URL: http://localhost:12000/sqoop/ Created by: didi Creation date: 2017-04-11 14:37:46 CST Lastly updated by: didi External ID: job_1491888730134_0003 http://jjzhu:8088/proxy/application_1491888730134_0003/ 2017-04-11 14:37:46 CST: BOOTING - Progress is not available

查看job运行状态

sqoop:002> status job -n job_weibouser Submission details Job Name: job_weibouser Server URL: http://localhost:12000/sqoop/ Created by: didi Creation date: 2017-04-11 14:37:46 CST Lastly updated by: didi External ID: job_1491888730134_0003 http://jjzhu:8088/proxy/application_1491888730134_0003/ 2017-04-11 14:38:41 CST: SUCCEEDED Counters: org.apache.hadoop.mapreduce.FileSystemCounter FILE_LARGE_READ_OPS: 0 FILE_WRITE_OPS: 0 HDFS_READ_OPS: 2 HDFS_BYTES_READ: 290 HDFS_LARGE_READ_OPS: 0 FILE_READ_OPS: 0 FILE_BYTES_WRITTEN: 51361466 FILE_BYTES_READ: 25115854 HDFS_WRITE_OPS: 2 HDFS_BYTES_WRITTEN: 24652721 org.apache.hadoop.mapreduce.lib.output.FileOutputFormatCounter BYTES_WRITTEN: 0 org.apache.hadoop.mapreduce.lib.input.FileInputFormatCounter BYTES_READ: 0 org.apache.hadoop.mapreduce.JobCounter TOTAL_LAUNCHED_MAPS: 2 VCORES_MILLIS_REDUCES: 20225 MB_MILLIS_MAPS: 27120640 TOTAL_LAUNCHED_REDUCES: 2 SLOTS_MILLIS_REDUCES: 20225 VCORES_MILLIS_MAPS: 26485 MB_MILLIS_REDUCES: 20710400 SLOTS_MILLIS_MAPS: 26485 MILLIS_REDUCES: 20225 OTHER_LOCAL_MAPS: 2 MILLIS_MAPS: 26485 org.apache.sqoop.submission.counter.SqoopCounters ROWS_READ: 109408 ROWS_WRITTEN: 109408 org.apache.hadoop.mapreduce.TaskCounter MAP_OUTPUT_MATERIALIZED_BYTES: 25115866 REDUCE_INPUT_RECORDS: 109408 SPILLED_RECORDS: 218816 MERGED_MAP_OUTPUTS: 4 VIRTUAL_MEMORY_BYTES: 0 MAP_INPUT_RECORDS: 0 SPLIT_RAW_BYTES: 290 FAILED_SHUFFLE: 0 MAP_OUTPUT_BYTES: 24762129 REDUCE_SHUFFLE_BYTES: 25115866 PHYSICAL_MEMORY_BYTES: 0 GC_TIME_MILLIS: 1648 REDUCE_INPUT_GROUPS: 109408 COMBINE_OUTPUT_RECORDS: 0 SHUFFLED_MAPS: 4 REDUCE_OUTPUT_RECORDS: 109408 MAP_OUTPUT_RECORDS: 109408 COMBINE_INPUT_RECORDS: 0 CPU_MILLISECONDS: 0 COMMITTED_HEAP_BYTES: 1951399936 Shuffle Errors CONNECTION: 0 WRONG_LENGTH: 0 BAD_ID: 0 WRONG_MAP: 0 WRONG_REDUCE: 0 IO_ERROR: 0 Job executed successfully

查看hdfs的相关路径，看是否有输出文件

jjzhu:~ didi$ hdfs dfs -ls /usr/jjzhu/spider Found 4 items drwxr-xr-x - didi supergroup 0 2017-04-11 14:38 /usr/jjzhu/spider/spiders_weibouser drwxr-xr-x - 777 supergroup 0 2017-04-11 10:58 /usr/jjzhu/spider/weibouser drwxr-xr-x - 777 supergroup 0 2017-04-11 13:33 /usr/jjzhu/spider/weobouser drwxr-xr-x - didi supergroup 0 2017-04-11 13:39 /usr/jjzhu/spider/weobouser2 jjzhu:~ didi$ hdfs dfs -ls /usr/jjzhu/spider/spiders_weibouser Found 2 items -rw-r--r-- 1 didi supergroup 12262783 2017-04-11 14:38 /usr/jjzhu/spider/spiders_weibouser/33b56441-b638-48cc-8d0d-37a808f25653.txt -rw-r--r-- 1 didi supergroup 12389938 2017-04-11 14:38 /usr/jjzhu/spider/spiders_weibouser/73b20d50-de72-4aea-8c8c-d97cdc48e667.txt

也可以访问hdfs的webui进行查看http://localhost:50070/

注意事项

定位问题一定要查看日志，sqoop的日志输出在sqoop.properties 配的路径sqoop.log

在配置hdfs文件路径的时候，确保有写权限通过如下命令修改hdfs下文件的权限 hdfs dfs -chown -R 777 HDFS_PATH RemoteException：User: xxx is not allowed to impersonate xxx

代理问题，确保hadoop的core-site.xml的xxx有代理

<property> <name>hadoop.proxyuser.XXX.hosts</name> <value>*</value> </property> <property> <name>hadoop.proxyuser.XXX.groups</name> <value>*</value> </property> 开启sqoop的详细异常日志 sqoop:000> set option --name verbose --value true status job -n jobname时报错：java.net.ConnectException: Call From xxx.xxx.xxx.xxx to 0.0.0.0:10020 failed on connection exception: java.net.ConnectException: Connection refuse

这个问题一般是在hadoop2.x版本里会出现，Hadoop的datanode需要访问namenode的jobhistory server,如果没有修改，则默认为0.0.0.0:10020，则可以修改mapred-site.xml文件

<property> <name>mapreduce.jobhistory.address</name>  <value>localhost:10020</value> </property> <property> <name>mapreduce.jobhistory.webapp.address</name>  <value>localhost:19888</value> </property>

启动jobhistory

$HADOOP_HOME/sbin/mr-jobhistory-daemon.sh start historyserver Error: Java heap space Container killed by the ApplicationMaster. Container killed on request. Exit code is 143.

确保mapredce有足够的java内存，可以在mapreduce-site.xml中配置

<property> <name>mapreduce.map.java.opts</name> <value>-Xmx1024m</value> </property> <property> <name>mapreduce.reduce.java.opts</name> <value>-Xmx1024m</value> </property> Exception has occurred during processing command Exception: org.apache.sqoop.common.SqoopException Message: GENERIC_JDBC_CONNECTOR_0016:Can't fetch schema -

解决：在创建mysql链接时，Identifier enclose：指定SQL中标识符的定界符，也就是说，有的SQL标示符是一个引号：select * from "table_name"，这种定界符在MySQL中是会报错的。这个属性默认值就是双引号，使用空格覆盖这个值。

参考: http://www.cnblogs.com/avivaye/p/6197123.html

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