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This article mainly introduces "what are the problems related to mysql5.6.15". In the daily operation, I believe many people have doubts about the problems related to mysql5.6.15. The editor consulted all kinds of materials and sorted out simple and easy-to-use methods of operation. I hope it will be helpful for you to answer the doubts about "what are the problems related to mysql5.6.15?" Next, please follow the editor to study!

Problem description 1:

Caused by: java.sql.SQLException: Unable to open a test connection to the given database. JDBC url = jdbc:mysql://192.168.64.11:3306/hive?characterEncoding=UTF-8, username = hive. Terminating connection pool (set lazyInit to true if you expect to start your database after your app). Original Exception:-

Com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception:

Cause of error: change the hive password after stopping the mysql service, and then do not restart mysql. Although you can log in with mysql-uroot-p on the host, running the hive command rejects the remote link.

Solution:

# / etc/init.d/mysql restart # restart the mysql service

Or service mysql restart

The above problems can be solved.

Problem description 2:

An error was reported when creating tables in Hive:

Create table years (year string, event string) row format delimited fields terminated by'\ t failed: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask. MetaException (m)

Character set problem, garbled, display character length problem, this is due to the character set problem, you need to configure the character set of MySQL:

Mysql > alter database hive character set latin1

The problem is solved after modification.

Problem description 3:

After hadoop is installed, you are often prompted with a warning:

WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... Using builtin-java classes where applicable

I searched a lot of articles and said that it had something to do with the number of bits of the system. I used the Centos 6.564-bit system.

First download hadoop-native-64-2.6.0.tar:

Http://dl.bintray.com/sequenceiq/sequenceiq-bin/hadoop-native-64-2.6.0.tar

After downloading, extract it to the native directory of hadoop and overwrite the original file. Do the following:

Tar-xvf hadoop-native-64-2.4.0.tar-C hadoop/lib/native/

Problem description 4:

FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask. MetaException (message:For direct MetaStore DB connections, we don't support retries at the client level.) This is because my mysql is no longer local (local database is used by default), so you need to configure the remote metadata server hive.metastore.uris thrift://10.24.32.169:9083.

Start the hive server program in the background

$nohup hive-service metastore &

The client can use the hive command directly

Problem description 5:

Java.lang.IllegalArgumentException: java.net.UnknownHostException: dfscluster solution: cannot find the hdfs cluster name dfscluster. This file is under the etc/hadoop of HADOOP. There is a file hdfs-site.xml. Copy it to the conf of hive, and restart it to [hadoop@slave4 hadoop] $cp hdfs-site.xml $HIVE_HOME/conf/.

Problem description 6:

Hive reported the following error when deleting the table: hive > drop table spider_log;FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask. MetaException (message:javax.jdo.JDODataStoreException: You have an error in your SQL syntax Check the manual that corresponds to your MySQL server version for the right syntax to use near 'OPTION SQL_SELECT_LIMIT=DEFAULT' at line 1 solution: this is caused by a mismatch between the version of mysql and the version of the driver. My mysql version is 5.6, and the driver I used at first is 5.1.18, but mysql5.6 has discarded this parameter, so it will report the above error and change it to driver mysql-connector-java-5.1.31-bin.jar. (note: a higher version of the driver may not work, I downloaded the driver is 5.1.51 can not be used, must be 5.1.31.) at this point, the study of "what are the problems related to mysql5.6.15" is over. I hope I can solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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