Hive的meta数据支持以下两种存储方式,文件存储和MySQL存储。
一、文件存储
这种方式是最简单的存储方式,只需要在hive-site.xml做如下配置便可
<?xml version="1.0"?> <?xml-stylesheet type="text/xsl" href="configuration.xsl"?> <configuration> <property> <name>javax.jdo.option.ConnectionURL</name> <value>jdbc:derby:;databaseName=metastore_db;create=true</value> </property> <property> <name>javax.jdo.option.ConnectionDriverName</name> <value>org.apache.derby.jdbc.EmbeddedDriver</value> </property> <property> <name>hive.metastore.local</name> <value>true</value> </property> <property> <name>hive.metastore.warehouse.dir</name> <value>/user/hive/warehouse</value> </property> <property> <name>hive.metastore.warehouse.dir</name> <value>/user/hive/warehouse</value> </property> </configuration>
注:使用derby存储方式时,运行hive会在当前目录生成一个derby文件和一个metastore_db目录。这种存储方式的弊端是在同一个目录下同时只能有一个hive客户端能使用数据库,否则会提示如下错误
hive> show tables; FAILED: Error in metadata: javax.jdo.JDOFatalDataStoreException: Failed to start database 'metastore_db', see the next exception for details. NestedThrowables: java.sql.SQLException: Failed to start database 'metastore_db', see the next exception for details. FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask
二、MySQL
这种存储方式需要在运行一个mysql服务器,并作如下配置(下面两种使用mysql的方式,需要将mysql的jar包拷贝到$HIVE_HOME/lib目录下)。
<?xml version="1.0"?> <?xml-stylesheet type="text/xsl" href="configuration.xsl"?> <configuration> <property> <name>hive.metastore.warehouse.dir</name> <value>V:/data/hive</value> </property> <property> <name>hive.metastore.local</name> <value>true</value> </property> <property> <name>javax.jdo.option.ConnectionURL</name> <value>jdbc:mysql://localhost/hive_remote?createDatabaseIfNotExist=true</value> </property> <property> <name>javax.jdo.option.ConnectionDriverName</name> <value>com.mysql.jdbc.Driver</value> </property> <property> <name>javax.jdo.option.ConnectionUserName</name> <value>root</value> </property> <property> <name>javax.jdo.option.ConnectionPassword</name> <value>xxxx</value> </property> </configuration>