使用MySQL作为Hive的Metastore

先确保你已经成功安装了HIVE和MYSQL

在hive-site.xml中添加如下内容，指定METASTORE的地址以及连接方式

<property>    
<name>javax.jdo.option.ConnectionURL</name>    
<value>jdbc:mysql://10.20.151.10:3306/hive?characterEncoding=UTF-8</value>    
<description>JDBC connect string for a JDBC metastore</description> 
</property> 
<property>    
<name>javax.jdo.option.ConnectionDriverName</name>    
<value>com.mysql.jdbc.Driver</value>    
<description>Driver class name for a JDBC metastore</description> 
</property> 
<property>    
<name>javax.jdo.option.ConnectionUserName</name>    
<value>hive_user</value>    
<description>username to use against metastore database</description> 
</property> 
<property>    
<name>javax.jdo.option.ConnectionPassword</name>    
<value>123</value>    
<description>password to use against metastore database</description> 
</property>

然后登陆到HIVE客户端，创建一个表试试

[gpadmin1@Hadoop5 hive-0.6.0]$ bin/hive
Hive history file=/tmp/gpadmin1/hive_job_log_gpadmin1_201106081130_1156785421.txt
hive> show tables;
FAILED: Error in metadata: javax.jdo.JDOFatalDataStoreException: Unknown database 'hive'
NestedThrowables:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database 'hive'
FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask

报错了，提示很明显，识别不到名称为hive的database，难道要自己创建？试试

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Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
4 rows in set (0.00 sec)

mysql> create database hive;
Query OK, 1 row affected (0.00 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| hive               |
| mysql              |
| performance_schema |
| test               |
+--------------------+
5 rows in set (0.00 sec)

再登陆到HIVE里看看

[gpadmin1@hadoop5 hive-0.6.0]$ bin/hive
Hive history file=/tmp/gpadmin1/hive_job_log_gpadmin1_201106081130_544334815.txt
hive> show table;                      
FAILED: Parse Error: line 0:-1 mismatched input '<EOF>' expecting EXTENDED in show statement

hive> show tables;
OK
Time taken: 5.173 seconds
hive>         CREATE TABLE u_tmp1 (id1 INT,
    >            id2 int
    >            )
    >          ROW FORMAT DELIMITED
    >          FIELDS TERMINATED BY ',';
OK
Time taken: 0.266 seconds
hive> show tables;                        
OK
u_tmp1
Time taken: 0.197 seconds
hive>

OK了，果然是这个问题