最近在搭一套Hive测试环境，使用mysql存储hive的元数据，然而当执行一个带有中文注释的建表文件时，出现了中文乱码的问题。实验过程中发现把整个数据库编码改成latin1或者Utf8都不行，只有把整个数据库设定为latin1而把要存储中文的数据表的编码设定为UTF8才能够解决。
出现问题：执行hive -f "createtable.sql"时说中文乱码不认识。
尝试1失败：将meta database（mysql）的编码全部设定为utf8
则报以下错误
——————-
FAILED: Error in metadata: javax.jdo.JDODataStoreException: An exception was thrown while adding/validating class(es) : Specified key was too long; max key length is 767 bytes
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Specified key was too long; max key length is 767 bytes
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1052)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3609)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3541)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2002)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2163)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2618)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2568)
at com.mysql.jdbc.StatementImpl.execute(StatementImpl.java:842)
at com.mysql.jdbc.StatementImpl.execute(StatementImpl.java:681)
at org.apache.commons.dbcp.DelegatingStatement.execute(DelegatingStatement.java:264)
at org.apache.commons.dbcp.DelegatingStatement.execute(DelegatingStatement.java:264)
at org.datanucleus.store.rdbms.table.AbstractTable.executeDdlStatement(AbstractTable.java:730)
at org.datanucleus.store.rdbms.table.AbstractTable.executeDdlStatementList(AbstractTable.java:681)
at org.datanucleus.store.rdbms.table.AbstractTable.create(AbstractTable.java:402)
at org.datanucleus.store.rdbms.table.AbstractTable.exists(AbstractTable.java:458)
at org.datanucleus.store.rdbms.RDBMSStoreManager$ClassAdder.performTablesValidation(RDBMSStoreManager.java:2689)
at org.datanucleus.store.rdbms.RDBMSStoreManager$ClassAdder.addClassTablesAndValidate(RDBMSStoreManager.java:2503)
at org.datanucleus.store.rdbms.RDBMSStoreManager$ClassAdder.run(RDBMSStoreManager.java:2148)
at org.datanucleus.store.rdbms.AbstractSchemaTransaction.execute(AbstractSchemaTransaction.java:113)
at org.datanucleus.store.rdbms.RDBMSStoreManager.addClasses(RDBMSStoreManager.java:986)
at org.datanucleus.store.rdbms.RDBMSStoreManager.addClasses(RDBMSStoreManager.java:952)
at org.datanucleus.store.AbstractStoreManager.addClass(AbstractStoreManager.java:919)
at org.datanucleus.store.mapped.MappedStoreManager.getDatastoreClass(MappedStoreManager.java:356)
at org.datanucleus.store.rdbms.query.legacy.ExtentHelper.getExtent(ExtentHelper.java:48)
at org.datanucleus.store.rdbms.RDBMSStoreManager.getExtent(RDBMSStoreManager.java:1332)
at org.datanucleus.ObjectManagerImpl.getExtent(ObjectManagerImpl.java:4149)
at org.datanucleus.store.rdbms.query.legacy.JDOQLQueryCompiler.compileCandidates(JDOQLQueryCompiler.java:411)
at org.datanucleus.store.rdbms.query.legacy.QueryCompiler.executionCompile(QueryCompiler.java:312)
at org.datanucleus.store.rdbms.query.legacy.JDOQLQueryCompiler.compile(JDOQLQueryCompiler.java:225)
at org.datanucleus.store.rdbms.query.legacy.JDOQLQuery.compileInternal(JDOQLQuery.java:175)
at org.datanucleus.store.query.Query.executeQuery(Query.java:1628)
at org.datanucleus.store.rdbms.query.legacy.JDOQLQuery.executeQuery(JDOQLQuery.java:245)
at org.datanucleus.store.query.Query.executeWithArray(Query.java:1499)
at org.datanucleus.jdo.JDOQuery.execute(JDOQuery.java:266)
at org.apache.hadoop.hive.metastore.ObjectStore.getMTable(ObjectStore.java:775)
at org.apache.hadoop.hive.metastore.ObjectStore.getTable(ObjectStore.java:709)
at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler.is_table_exists(HiveMetaStore.java:965)
at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler.create_table_core(HiveMetaStore.java:887)
at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler.access$600(HiveMetaStore.java:109)
at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler$15.run(HiveMetaStore.java:945)
at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler$15.run(HiveMetaStore.java:942)
at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler.executeWithRetry(HiveMetaStore.java:307)
at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler.create_table(HiveMetaStore.java:942)
at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.createTable(HiveMetaStoreClient.java:348)
at org.apache.hadoop.hive.ql.metadata.Hive.createTable(Hive.java:469)
at org.apache.hadoop.hive.ql.exec.DDLTask.createTable(DDLTask.java:3149)
at org.apache.hadoop.hive.ql.exec.DDLTask.execute(DDLTask.java:213)
at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:130)
at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:57)
at org.apache.hadoop.hive.ql.Driver.launchTask(Driver.java:1063)
at org.apache.hadoop.hive.ql.Driver.execute(Driver.java:900)
at org.apache.hadoop.hive.ql.Driver.run(Driver.java:748)
at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:165)
at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:246)
at org.apache.hadoop.hive.cli.CliDriver.processReader(CliDriver.java:267)
at org.apache.hadoop.hive.cli.CliDriver.processFile(CliDriver.java:274)
at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:435)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.hadoop.mapred.util.RunJar.main(RunJar.java:210)
at org.apache.hadoop.mapred.JobShell.run(JobShell.java:54)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:79)
at org.apache.hadoop.mapred.JobShell.main(JobShell.java:68)
NestedThrowables:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Specified key was too long; max key length is 767 bytes
FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask
——————-
尝试2失败：将meta server（mysql）的编码全部设定为latin1
则报以下错误：
———
[[email protected] sql]$ hive -f crazyant.sql
Hive history file=/tmp/crazyant/hive_job_log_crazyant_20130904.txt
OK
Time taken: 2.064 seconds
FAILED: Error in metadata: javax.jdo.JDODataStoreException: Add request failed : INSERT INTO COLUMNS (SD_ID,COMMENT,COLUMN_NAME,TYPE_NAME,INTEGER_IDX) VALUES (?,?,?,?,?)
NestedThrowables:
java.sql.BatchUpdateException: Incorrect string value: ‘\xC2\x8A\xC2\xA8\xC3\xA7…’ for column ‘COMMENT’ at row 1
FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask
———
解决方案：数据库编码为latin1，COLUMNS表和TABLE_PARAMS表编码设定为UTF8
1、首先按照latin1编码建立hive的meta数据库；
2、修改hive-default.xml的连接编码为UTF8；
3、然后进入数据库执行以下两条SQL语句：
| 该语句将HIVE的COLUMNS 表的column 列改成UTF8编码 |
| alter table COLUMNS modify column COMMENT varchar(256) character set utf8 |
| 该语句将HIVE的TABLE_PARAMS 表的PARAM_VALUE 列改成UTF8编码 |
| alter table TABLE_PARAMS modify column PARAM_VALUE varchar(4000) character set utf8 |
执行完后用hive -f create_table.sql 中文乱码没有出现，进入数据库执行desc table；语句也没有出现乱码。
问题解决。