Hive的访问接口 | Allen's World

Hive的访问接口 | Allen's World

Hive的访问接口

Hive提供了三种客户端访问接口：

1）Hive CLI（Hive Command Line，Hive命令行），客户端可以直接在命令行模式下进行操作。

2）hwi（Hive Web Interface，Hive Web接口），Hive提供了更直观的Web界面

3）hiveserver，Hive提供了Thrift服务，Thrift客户端目前支持C++/Java/PHP/Python/Ruby。

下面我们来分别尝试下这三种接口访问方式：

一、Hive CLI

直接键入hive命令即可进入CLI模式：

[cloud@cloud01 lib]$ hive

Hive history file=/tmp/cloud/hive_job_log_cloud_201110311056_1009535967.txt

hive> show tables;

OK

testhivedrivertable

Time taken: 3.038 seconds

hive> select * from testhivedrivertable;

OK

Time taken: 0.905 seconds

hive> quit;

[cloud@cloud01 lib]$

更多的命令选项，参见官方wiki，Hive Cli

二、Hive hwi

Hive hwi提供了一个更直观的web界面，使用起来更方便。

1）启动hive hwi

[cloud@cloud01 ~]$ hive --service hwi

11/10/31 10:14:11 INFO hwi.HWIServer: HWI is starting up

11/10/31 10:14:11 INFO mortbay.log: Logging to org.slf4j.impl.Log4jLoggerAdapter(org.mortbay.log) via org.mortbay.log.Slf4jLog

11/10/31 10:14:11 INFO mortbay.log: jetty-6.1.14

11/10/31 10:14:11 INFO mortbay.log: Extract jar:file:/data/cloud/hive-0.7.1/lib/hive-hwi-0.7.1.war!/ to /tmp/Jetty_0_0_0_0_9999_hive.hwi.0.7.1.war__hwi__.hf8ccz/webapp

11/10/31 10:14:12 INFO mortbay.log: Started SocketConnector@0.0.0.0:9999

2）通过hwi方式访问Hive

我的Hive部署在10.46.169.101机器上，hive默认hwi端口为9999。我们在浏览器中键入http://10.46.169.101:9999/hwi/ 就可以访问了。如图：

更多hwi的信息，访问官方wiki，hwi

三、hiveserver

Hive以Thrift方式作为服务对客户端提供，目前Hive的Thrift绑定了多种语言，C++/Java/PHP/Python/Ruby，可在Hive发行版本的src/service/src目录下找到这些语言的Thrift绑定。Hive还提供了JDBC和ODBC的驱动，大大方面了基于Hive的应用开发。我利用官方的例子对JDBC驱动进行了测试。

1）启动hiveserver

[cloud@cloud01 ~]$ hive --service hiveserver

Starting Hive Thrift Server

2）在Eclipse中新建一个Java工程Hive0.7.1Test

3）将$HIVE_HOME/lib目录下的jar包加到工程的buildpath里

4）Hive的表是存储在HDFS上，所以，需要加载Hadoop的核心jar包。我的Hadoop版本是0.20.1。

5）新建一个class，用官方wiki提供的代码，如下：

import java.sql.SQLException;

import java.sql.Connection;

import java.sql.ResultSet;

import java.sql.Statement;

import java.sql.DriverManager;

public class HiveJdbcClient {

private static String driverName = "org.apache.hadoop.hive.jdbc.HiveDriver";

/**

* @param args

* @throws SQLException

*/

public static void main(String[] args) throws SQLException {

try {

Class.forName(driverName);

} catch (ClassNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

System.exit(1);

}

Connection con = DriverManager.getConnection(

"jdbc:hive://10.46.169.101:10000/default", "", "");

Statement stmt = con.createStatement();

String tableName = "testHiveDriverTable";

stmt.executeQuery("drop table " + tableName);

ResultSet res = stmt.executeQuery("create table " + tableName

+ " (key int, value string)");

// show tables

String sql = "show tables '" + tableName + "'";

System.out.println("Running: " + sql);

res = stmt.executeQuery(sql);

if (res.next()) {

System.out.println(res.getString(1));

}

// describe table

sql = "describe " + tableName;

System.out.println("Running: " + sql);

res = stmt.executeQuery(sql);

while (res.next()) {

System.out.println(res.getString(1) + "\t" + res.getString(2));

}

// load data into table

// NOTE: filepath has to be local to the hive server

// NOTE: /tmp/a.txt is a ctrl-A separated file with two fields per line

String filepath = "/tmp/a.txt";

sql = "load data local inpath '" + filepath + "' into table "

+ tableName;

System.out.println("Running: " + sql);

res = stmt.executeQuery(sql);

// select * query

sql = "select * from " + tableName;

System.out.println("Running: " + sql);

res = stmt.executeQuery(sql);

while (res.next()) {

System.out.println(String.valueOf(res.getInt(1)) + "\t"

+ res.getString(2));

}

// regular hive query

sql = "select count(1) from " + tableName;

System.out.println("Running: " + sql);

res = stmt.executeQuery(sql);

while (res.next()) {

System.out.println(res.getString(1));

}

}

}

6）编译运行，console如下：

<div>2011-10-31 11:21:31,703 WARN  [main] conf.Configuration(175): DEPRECATED: hadoop-site.xml found in the classpath. Usage of hadoop-site.xml is deprecated. Instead use core-site.xml, mapred-site.xml and hdfs-site.xml to override properties of core-default.xml, mapred-default.xml and hdfs-default.xml respectively</div>
<div>Running: show tables 'testHiveDriverTable'</div>
<div>testhivedrivertable</div>
<div>Running: describe testHiveDriverTable</div>
<div>keyint</div>
<div>valuestring</div>
<div>Running: load data local inpath '/tmp/a.txt' into table testHiveDriverTable</div>
<div>Exception in thread "main" java.sql.SQLException: Query returned non-zero code: 10, cause: FAILED: Error in semantic analysis: Line 1:23 Invalid path '/tmp/a.txt': No files matching path file:/tmp/a.txt</div>
<div>at org.apache.hadoop.hive.jdbc.HiveStatement.executeQuery(HiveStatement.java:192)</div>
<div>at com.zte.allen.hive.HiveJdbcClient.main(HiveJdbcClient.java:53)</div>

报了一个Exception，是因为加载源是找不到/tmp/a.txt。这个不影响，但可以从hwi里看到已经新建了一个表testhivedrivertable。

更多关于hiveserver的内容，参见官方wiki Setting up Hive Server, 还有这里介绍了各种客户端（cli、Java、PHP、Python、ODBC、Thrift方式等）如何访问Hive。