Caused by: java.net.ConnectException: Connection refused/Caused by: java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
1、使用sqoop技术将mysql的数据导入到Hive出现的错误如下所示：
第一次使用命令如下所示：
[hadoop@slaver1 sqoop-1.4.-cdh5.3.6]$ bin/sqoop import --connect jdbc:mysql://localhost:3306/test --username root --password 123456 --table tb_user --hive-import --m 1
Warning: /home/hadoop/soft/sqoop-1.4.-cdh5.3.6/../hcatalog does not exist! HCatalog jobs will fail.
Please set $HCAT_HOME to the root of your HCatalog installation.
Warning: /home/hadoop/soft/sqoop-1.4.-cdh5.3.6/../accumulo does not exist! Accumulo imports will fail.
Please set $ACCUMULO_HOME to the root of your Accumulo installation.
// :: INFO sqoop.Sqoop: Running Sqoop version: 1.4.-cdh5.3.6
// :: WARN tool.BaseSqoopTool: Setting your password on the command-line is insecure. Consider using -P instead.
// :: INFO tool.BaseSqoopTool: Using Hive-specific delimiters for output. You can override
// :: INFO tool.BaseSqoopTool: delimiters with --fields-terminated-by, etc.
// :: INFO manager.MySQLManager: Preparing to use a MySQL streaming resultset.
// :: INFO tool.CodeGenTool: Beginning code generation
// :: INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `tb_user` AS t LIMIT
// :: INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `tb_user` AS t LIMIT
// :: INFO orm.CompilationManager: HADOOP_MAPRED_HOME is /home/hadoop/soft/hadoop-2.5.-cdh5.3.6
Note: /tmp/sqoop-hadoop/compile/cb8f61449b0ae521eecbd2bccba40b07/tb_user.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
// :: INFO orm.CompilationManager: Writing jar file: /tmp/sqoop-hadoop/compile/cb8f61449b0ae521eecbd2bccba40b07/tb_user.jar
// :: WARN manager.MySQLManager: It looks like you are importing from mysql.
// :: WARN manager.MySQLManager: This transfer can be faster! Use the --direct
// :: WARN manager.MySQLManager: option to exercise a MySQL-specific fast path.
// :: INFO manager.MySQLManager: Setting zero DATETIME behavior to convertToNull (mysql)
// :: INFO mapreduce.ImportJobBase: Beginning import of tb_user
// :: WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
// :: INFO Configuration.deprecation: mapred.jar is deprecated. Instead, use mapreduce.job.jar
// :: INFO Configuration.deprecation: mapred.map.tasks is deprecated. Instead, use mapreduce.job.maps
// :: INFO client.RMProxy: Connecting to ResourceManager at slaver1/192.168.19.131:
// :: INFO db.DBInputFormat: Using read commited transaction isolation
// :: INFO mapreduce.JobSubmitter: number of splits:
// :: INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1526642793183_0002
// :: INFO impl.YarnClientImpl: Submitted application application_1526642793183_0002
// :: INFO mapreduce.Job: The url to track the job: http://slaver1:8088/proxy/application_1526642793183_0002/
// :: INFO mapreduce.Job: Running job: job_1526642793183_0002
// :: INFO mapreduce.Job: Job job_1526642793183_0002 running in uber mode : false
// :: INFO mapreduce.Job: map % reduce %
// :: INFO mapreduce.Job: Task Id : attempt_1526642793183_0002_m_000000_0, Status : FAILED
Error: java.lang.RuntimeException: java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at org.apache.sqoop.mapreduce.db.DBInputFormat.setConf(DBInputFormat.java:)
at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:)
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:)
at org.apache.hadoop.mapred.YarnChild$.run(YarnChild.java:)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:)
Caused by: java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at org.apache.sqoop.mapreduce.db.DBInputFormat.getConnection(DBInputFormat.java:)
at org.apache.sqoop.mapreduce.db.DBInputFormat.setConf(DBInputFormat.java:)
... more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:)
at java.lang.reflect.Constructor.newInstance(Constructor.java:)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:)
at java.lang.reflect.Constructor.newInstance(Constructor.java:)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:)
at java.sql.DriverManager.getConnection(DriverManager.java:)
at java.sql.DriverManager.getConnection(DriverManager.java:)
at org.apache.sqoop.mapreduce.db.DBConfiguration.getConnection(DBConfiguration.java:)
at org.apache.sqoop.mapreduce.db.DBInputFormat.getConnection(DBInputFormat.java:)
... more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:)
at java.net.Socket.connect(Socket.java:)
at java.net.Socket.connect(Socket.java:)
at java.net.Socket.<init>(Socket.java:)
at java.net.Socket.<init>(Socket.java:)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:)
... more // :: INFO mapreduce.Job: Task Id : attempt_1526642793183_0002_m_000000_1, Status : FAILED
Error: java.lang.RuntimeException: java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at org.apache.sqoop.mapreduce.db.DBInputFormat.setConf(DBInputFormat.java:)
at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:)
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:)
at org.apache.hadoop.mapred.YarnChild$.run(YarnChild.java:)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:)
Caused by: java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at org.apache.sqoop.mapreduce.db.DBInputFormat.getConnection(DBInputFormat.java:)
at org.apache.sqoop.mapreduce.db.DBInputFormat.setConf(DBInputFormat.java:)
... more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:)
at java.lang.reflect.Constructor.newInstance(Constructor.java:)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:)
at java.lang.reflect.Constructor.newInstance(Constructor.java:)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:)
at java.sql.DriverManager.getConnection(DriverManager.java:)
at java.sql.DriverManager.getConnection(DriverManager.java:)
at org.apache.sqoop.mapreduce.db.DBConfiguration.getConnection(DBConfiguration.java:)
at org.apache.sqoop.mapreduce.db.DBInputFormat.getConnection(DBInputFormat.java:)
... more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:)
at java.net.Socket.connect(Socket.java:)
at java.net.Socket.connect(Socket.java:)
at java.net.Socket.<init>(Socket.java:)
at java.net.Socket.<init>(Socket.java:)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:)
... more // :: INFO mapreduce.Job: Task Id : attempt_1526642793183_0002_m_000000_2, Status : FAILED
Error: java.lang.RuntimeException: java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at org.apache.sqoop.mapreduce.db.DBInputFormat.setConf(DBInputFormat.java:)
at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:)
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:)
at org.apache.hadoop.mapred.YarnChild$.run(YarnChild.java:)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:)
Caused by: java.lang.RuntimeException: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at org.apache.sqoop.mapreduce.db.DBInputFormat.getConnection(DBInputFormat.java:)
at org.apache.sqoop.mapreduce.db.DBInputFormat.setConf(DBInputFormat.java:)
... more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet sent successfully to the server was milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:)
at java.lang.reflect.Constructor.newInstance(Constructor.java:)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:)
at java.lang.reflect.Constructor.newInstance(Constructor.java:)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:)
at java.sql.DriverManager.getConnection(DriverManager.java:)
at java.sql.DriverManager.getConnection(DriverManager.java:)
at org.apache.sqoop.mapreduce.db.DBConfiguration.getConnection(DBConfiguration.java:)
at org.apache.sqoop.mapreduce.db.DBInputFormat.getConnection(DBInputFormat.java:)
... more
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:)
at java.net.Socket.connect(Socket.java:)
at java.net.Socket.connect(Socket.java:)
at java.net.Socket.<init>(Socket.java:)
at java.net.Socket.<init>(Socket.java:)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:)
... more ^C[hadoop@slaver1 sqoop-1.4.-cdh5.3.6]$
2、第二次导入使用命令如：
主要是注意连接的主机名称别写错了，账号和密码信息。
[hadoop@slaver1 sqoop-1.4.-cdh5.3.6]$ bin/sqoop import \
> --connect jdbc:mysql://slaver1:3306/test \
> --username root \
> --password \
> --table tb_user \
> --hive-import \
> --m
Warning: /home/hadoop/soft/sqoop-1.4.-cdh5.3.6/../hcatalog does not exist! HCatalog jobs will fail.
Please set $HCAT_HOME to the root of your HCatalog installation.
Warning: /home/hadoop/soft/sqoop-1.4.-cdh5.3.6/../accumulo does not exist! Accumulo imports will fail.
Please set $ACCUMULO_HOME to the root of your Accumulo installation.
// :: INFO sqoop.Sqoop: Running Sqoop version: 1.4.-cdh5.3.6
// :: WARN tool.BaseSqoopTool: Setting your password on the command-line is insecure. Consider using -P instead.
// :: INFO tool.BaseSqoopTool: Using Hive-specific delimiters for output. You can override
// :: INFO tool.BaseSqoopTool: delimiters with --fields-terminated-by, etc.
// :: INFO manager.MySQLManager: Preparing to use a MySQL streaming resultset.
// :: INFO tool.CodeGenTool: Beginning code generation
// :: INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `tb_user` AS t LIMIT
// :: INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `tb_user` AS t LIMIT
// :: INFO orm.CompilationManager: HADOOP_MAPRED_HOME is /home/hadoop/soft/hadoop-2.5.-cdh5.3.6
Note: /tmp/sqoop-hadoop/compile/02d8e06c0a500fbe72ac09d7f0dca9c3/tb_user.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
// :: INFO orm.CompilationManager: Writing jar file: /tmp/sqoop-hadoop/compile/02d8e06c0a500fbe72ac09d7f0dca9c3/tb_user.jar
// :: WARN manager.MySQLManager: It looks like you are importing from mysql.
// :: WARN manager.MySQLManager: This transfer can be faster! Use the --direct
// :: WARN manager.MySQLManager: option to exercise a MySQL-specific fast path.
// :: INFO manager.MySQLManager: Setting zero DATETIME behavior to convertToNull (mysql)
// :: INFO mapreduce.ImportJobBase: Beginning import of tb_user
// :: WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
// :: INFO Configuration.deprecation: mapred.jar is deprecated. Instead, use mapreduce.job.jar
// :: INFO Configuration.deprecation: mapred.map.tasks is deprecated. Instead, use mapreduce.job.maps
// :: INFO client.RMProxy: Connecting to ResourceManager at slaver1/192.168.19.131:
// :: INFO db.DBInputFormat: Using read commited transaction isolation
// :: INFO mapreduce.JobSubmitter: number of splits:
// :: INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1526642793183_0003
// :: INFO impl.YarnClientImpl: Submitted application application_1526642793183_0003
// :: INFO mapreduce.Job: The url to track the job: http://slaver1:8088/proxy/application_1526642793183_0003/
// :: INFO mapreduce.Job: Running job: job_1526642793183_0003
// :: INFO mapreduce.Job: Job job_1526642793183_0003 running in uber mode : false
// :: INFO mapreduce.Job: map % reduce %
// :: INFO mapreduce.Job: map % reduce %
// :: INFO mapreduce.Job: Job job_1526642793183_0003 completed successfully
// :: INFO mapreduce.Job: Counters:
File System Counters
FILE: Number of bytes read=
FILE: Number of bytes written=
FILE: Number of read operations=
FILE: Number of large read operations=
FILE: Number of write operations=
HDFS: Number of bytes read=
HDFS: Number of bytes written=
HDFS: Number of read operations=
HDFS: Number of large read operations=
HDFS: Number of write operations=
Job Counters
Launched map tasks=
Other local map tasks=
Total time spent by all maps in occupied slots (ms)=
Total time spent by all reduces in occupied slots (ms)=
Total time spent by all map tasks (ms)=
Total vcore-seconds taken by all map tasks=
Total megabyte-seconds taken by all map tasks=
Map-Reduce Framework
Map input records=
Map output records=
Input split bytes=
Spilled Records=
Failed Shuffles=
Merged Map outputs=
GC time elapsed (ms)=
CPU time spent (ms)=
Physical memory (bytes) snapshot=
Virtual memory (bytes) snapshot=
Total committed heap usage (bytes)=
File Input Format Counters
Bytes Read=
File Output Format Counters
Bytes Written=
// :: INFO mapreduce.ImportJobBase: Transferred bytes in 27.1712 seconds (5.631 bytes/sec)
// :: INFO mapreduce.ImportJobBase: Retrieved records.
// :: INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `tb_user` AS t LIMIT
// :: INFO hive.HiveImport: Loading uploaded data into Hive
// :: INFO hive.HiveImport:
// :: INFO hive.HiveImport: Logging initialized using configuration in jar:file:/home/hadoop/soft/hive-0.13.-cdh5.3.6/lib/hive-common-0.13.-cdh5.3.6.jar!/hive-log4j.properties
// :: INFO hive.HiveImport: OK
// :: INFO hive.HiveImport: Time taken: 4.423 seconds
// :: INFO hive.HiveImport: Loading data to table default.tb_user
// :: INFO hive.HiveImport: Table default.tb_user stats: [numFiles=, numRows=, totalSize=, rawDataSize=]
// :: INFO hive.HiveImport: OK
// :: INFO hive.HiveImport: Time taken: 1.68 seconds
// :: INFO hive.HiveImport: Hive import complete.
// :: INFO hive.HiveImport: Export directory is not empty, keeping it.
[hadoop@slaver1 sqoop-1.4.-cdh5.3.6]$
3、由于mysql导入到Hive中模式是在default中，所以查看的时候可以去default数据库中查看。
[hadoop@slaver1 ~]$ hive Logging initialized using configuration in jar:file:/home/hadoop/soft/hive-0.13.-cdh5.3.6/lib/hive-common-0.13.-cdh5.3.6.jar!/hive-log4j.properties
hive> show databases;
OK
course
default
test0516
test20180509
Time taken: 0.759 seconds, Fetched: row(s)
hive> use default;
OK
Time taken: 0.025 seconds
hive> show tables;
OK
tb_user
user
Time taken: 0.035 seconds, Fetched: row(s)
hive> select * from tb_user;
OK
张三
李四
王五
小明
小红
小别 Time taken: 1.14 seconds, Fetched: row(s)
hive>
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