无法从 Eclipse 建立到 Hive 的 JDBC 连接 [英] Unable to establish a JDBC connection to Hive from Eclipse

问题描述

我正在尝试建立到 Hive 的 JDBC 连接，以便我可以从 Eclipse 查看和创建表以及查询 Hive 表.我使用了 HiveClient 示例代码:https://cwiki.apache.org/confluence/display/Hive/HiveClient然后我将所有必需的 jars 添加到 eclipse 中的 java 构建路径并启动 Hive Thrift Server.端口 10000 正在侦听.我正在使用 Cloudera QuickstartVM 4.6.1 和它附带的 eclipse.这是我尝试运行代码时在 IDE 中遇到的错误.

I am trying to establish a JDBC connection to Hive so that I can view and create tables and query Hive tables from Eclipse. I used HiveClient sample code: https://cwiki.apache.org/confluence/display/Hive/HiveClient Then I added all the required jars to the java build path inside eclipse and started Hive Thrift Server. Port 10000 is listening. I am using Cloudera QuickstartVM 4.6.1 and the eclipse that comes with it. Here's the error that I get in the IDE when I try to run the code.

Exception in thread "main" java.sql.SQLException: org.apache.thrift.transport.TTransportException: java.net.SocketException: Connection reset
    at org.apache.hadoop.hive.jdbc.HiveStatement.executeQuery(HiveStatement.java:191)
    at org.apache.hadoop.hive.jdbc.HiveStatement.execute(HiveStatement.java:127)
    at org.apache.hadoop.hive.jdbc.HiveConnection.configureConnection(HiveConnection.java:108)
    at org.apache.hadoop.hive.jdbc.HiveConnection.<init>(HiveConnection.java:103)
    at org.apache.hadoop.hive.jdbc.HiveDriver.connect(HiveDriver.java:104)
    at java.sql.DriverManager.getConnection(DriverManager.java:582)
    at java.sql.DriverManager.getConnection(DriverManager.java:185)
    at jdbc.Hive.main(Hive.java:24)

当我尝试使用直线连接到 Hive 时，我遇到了同样的错误.但是，当我从 !connect 命令中删除主机名和端口时，它会出现以下错误:

When I try connecting to Hive using beeline, I get the same error. However, when I eliminate the host name and port from the !connect command it works with the following error:

beeline> !connect jdbc:hive:// "" ""                 
scan complete in 4ms
Connecting to jdbc:hive://
14/03/21 18:42:03 WARN conf.HiveConf: DEPRECATED: Configuration property hive.metastore.local no longer has any effect. Make sure to provide a valid value for hive.metastore.uris if you are connecting to a remote metastore.
14/03/21 18:42:03 INFO metastore.HiveMetaStore: 0: Opening raw store with implemenation class:org.apache.hadoop.hive.metastore.ObjectStore
14/03/21 18:42:04 INFO metastore.ObjectStore: ObjectStore, initialize called
14/03/21 18:42:05 INFO DataNucleus.Persistence: Property datanucleus.cache.level2 unknown - will be ignored.

我在这里错过了什么！?

What am I missing here!?

推荐答案

You have 2 options to connect hiveserver using jdbc

You have 2 options to connect hiveserver using jdbc

选项 1:Hiveserver2

Option 1 : Hiveserver2

您正在尝试连接hiveserver2，cloudera manager中的hiveserver版本是hivesever2，比hiveserver更安全.你使用的JDBC代码是hiveserver，hiveserver2使用如下代码片段

You are trying to connect hiveserver2, hiveserver version in cloudera manager is hivesever2, which is more secure than hiveserver. JDBC code you are using is hiveserver,Use the following code snippet for hiveserver2

Class.forName("org.apache.hive.jdbc.HiveDriver");
Connection con = DriverManager.getConnection("jdbc:hive2://localhost:10000/default", "hive", "");
Statement stmt = con.createStatement();
String tableName = "testHiveDriverTable";
stmt.execute("drop table if exists " + tableName);
stmt.execute("create table " + tableName + " (key int, value string)");
String sql = "show tables '" + tableName + "'";

如果查看连接字符串，可以看到hiveserver version 2(jdbc:hive2://localhost:10000/default", "", "")，第二个和第三个参数是用户名和密码，默认为空字符串"".

If you look at the connection string, can see the hiveserver version 2(jdbc:hive2://localhost:10000/default", "", ""), second and third arguments are username and password, by default keep it empty string "".

为了执行这个程序，添加 hiveserver2 特定的库.

For executing this program add hiveserver2 specific libraries.

可以使用 beeline hive 客户端，而不是编写自己的程序来检查 hiveserver2 jdbc 连接

Instead of writing your own programs for checking hiveserver2 jdbc connection, beeline hive client can be used as follows

> [testuser02@Abcd-Host1 ~]$ beeline

> beeline> !connect jdbc:hive2://Abcd-Host1:10000/default "" "" ""
> 
> 0: jdbc:hive2://Abcd-Host1:10000/default> show tables;

+------------+
|  tab_name  |
+------------+
| sample_07  |
| sample_08  |
| test1      |
+------------+
3 rows selected (0.334 seconds)

选项 2:Hiveserver1

Options 2: Hiveserver1

如果你想使用你现有的代码(hiveserver1 的代码)，你有 https://cwiki.apache.org/confluence/display/Hive/HiveClient.您必须在另一个端口的用户空间中启动一个新的 hiveserver.使用以下命令在给定端口启动 hiveserver

If you want to make use of your existing code(code for hiveserver1), which you are having https://cwiki.apache.org/confluence/display/Hive/HiveClient. You got to start a new hiveserver in your userspace in another port. Use the following command to start a hiveserver in a given port

nohup hive --service hiveserver -p 10001 &

nohup hive --service hiveserver -p 10001 &

现在将 jdbc 连接中的端口号更改为 10001 并运行它.

Now change the port number to 10001 in jdbc connection and run it.

这篇关于无法从 Eclipse 建立到 Hive 的 JDBC 连接的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！