Phoenix JDBC开发
作者:互联网
Apache Phoenix
- Apache Phoenix基于HBase的一个SQL引擎,我们可以使用Phoenix在HBase之上提供SQL语言的支持。
- Phoenix是可以支持二级索引的,而且Phoenix它自动帮助我们管理二级索引,底层是通过HBase的协处理器来实现的,通过配合二级索引和HBase rowkey,可以提升hbase的查询效率
- Phoenix底层还是将SQL语言解析为HBase的原生查询(put/get/scan),所以它的定位还是在随机实时查询——OLTP领域
- Apache Phoenix不是独立运行的,而是提供一些JAR包,扩展了HBase的功能
Phoenix的建表语法
在Phoenix中,要执行SQL,必须要建立表的结构,然后才能查询。默认Phoenix不会之前在Hbase使用create创建的表加载进来。
create table if not exists ORDER_DTL(
"id" varchar primary key,
"C1"."status" varchar,
"C1"."money" double,
"C1"."pay_way" integer,
"C1"."user_id" varchar,
"C1"."operation_time" varchar,
"C1"."category" varchar
);
注意事项:
- 每个表必须要有rowkey,通过指定某一个列后面的primary key,就表示该列就是rowkey
- 每个除了rowkey的列必须要带列蔟名,Phoenix会自动帮助我们创建列蔟
- 大小写的问题,在Phoenix如果要使用小写,必须得带双引号。否则会自动转换为大小,如果使用小写将来编写的任何SQL语句都得带双引号
Phoenix创建视图
-
将HBase已经存在的表进行映射
-
名称空间和表名一模一样
-
列蔟名和列名也必须要一一对应
create view "名称空间"."表名"(
rowkey对应列名 varchar primary key,
"列蔟名"."列名" varchar,
);
创建跟之前一样的的视图
create view if not exists "MOMO_CHAT"."MSG"(
id varchar primary key,
"C1"."msg_time" varchar,
"C1"."sender_nickyname" varchar,
"C1"."sender_account" varchar,
"C1"."sender_sex" varchar,
"C1"."sender_ip" varchar,
"C1"."sender_os" varchar,
"C1"."sender_phone_type" varchar,
"C1"."sender_network" varchar,
"C1"."sender_gps" varchar,
"C1"."receiver_nickyname" varchar,
"C1"."receiver_ip" varchar,
"C1"."receiver_account" varchar,
"C1"."receiver_os" varchar,
"C1"."receiver_phone_type" varchar,
"C1"."receiver_network" varchar,
"C1"."receiver_gps" varchar,
"C1"."receiver_sex" varchar,
"C1"."msg_type" varchar,
"C1"."distance" varchar,
"C1"."message" varchar
);
Table is read only异常解决
这个时候遇到一个异常:Table is read only
- 在
hbase-site.xml
添加如下配置
<property>
<name>phoenix.schema.isNamespaceMappingEnabled</name>
<value>true</value>
</property>
<property>
<name>phoenix.schema.mapSystemTablesToNamespace</name>
<value>true</value>
</property>
- 复制到phoneix目录下一份
cp hbase-site.xml /apache-phoenix-4.13.1-HBase-1.3-bin/bin/
- 再重新执行下建表命令,可以了
使用jdbc开发
- pom新增phonex 依赖配置
<dependency>
<groupId>org.apache.phoenix</groupId>
<artifactId>phoenix-core</artifactId>
<version>4.13.1-HBase-1.3</version>
</dependency>
<!-- phoenix 客户端 -->
<dependency>
<groupId>org.apache.phoenix</groupId>
<artifactId>phoenix-queryserver-client</artifactId>
<version>4.13.1-HBase-1.3</version>
</dependency>
- 核心查询逻辑
public class PhoenixChatMessageService implements ChatMessageService {
private Connection connection;
public PhoenixChatMessageService() throws Exception {
// 1. 加载驱动
Class.forName(PhoenixDriver.class.getName());
// 2. 获取JDBC连接
Properties props = new Properties();
props.setProperty("phoenix.schema.isNamespaceMappingEnabled", "true");
connection = DriverManager.getConnection("jdbc:phoenix:master:2181",props);
}
@Override
public List<Msg> getMessage(String date, String sender, String receiver) throws Exception {
// 1. SQL语句
String sql = "select * from \"MOMO_CHAT\".\"MSG\" where substr(\"msg_time\", 0, 10) = ? and \"sender_account\" = ? and \"receiver_account\" = ?";
// 2. 构建一个prepareStatement
PreparedStatement preparedStatement = connection.prepareStatement(sql);
// 3. 设置Prestatement对应的参数
preparedStatement.setString(1, date);
preparedStatement.setString(2, sender);
preparedStatement.setString(3, receiver);
// 4. 执行SQL语句,获取到一个ResultSet
ResultSet resultSet = preparedStatement.executeQuery();
ArrayList<Msg> msgList = new ArrayList<>();
// 5. 迭代ResultSet将数据封装在Msg里面
while(resultSet.next()) {
Msg msg = new Msg();
msg.setMsg_time(resultSet.getString("msg_time"));
msg.setSender_nickyname(resultSet.getString("sender_nickyname"));
msg.setSender_account(resultSet.getString("sender_account"));
msg.setSender_sex(resultSet.getString("sender_sex"));
msg.setSender_ip(resultSet.getString("sender_ip"));
msg.setSender_os(resultSet.getString("sender_os"));
msg.setSender_phone_type(resultSet.getString("sender_phone_type"));
msg.setSender_network(resultSet.getString("sender_network"));
msg.setSender_gps(resultSet.getString("sender_gps"));
msg.setReceiver_nickyname(resultSet.getString("receiver_nickyname"));
msg.setReceiver_ip(resultSet.getString("receiver_ip"));
msg.setReceiver_account(resultSet.getString("receiver_account"));
msg.setReceiver_os(resultSet.getString("receiver_os"));
msg.setReceiver_phone_type(resultSet.getString("receiver_phone_type"));
msg.setReceiver_network(resultSet.getString("receiver_network"));
msg.setReceiver_gps(resultSet.getString("receiver_gps"));
msg.setReceiver_sex(resultSet.getString("receiver_sex"));
msg.setMsg_type(resultSet.getString("msg_type"));
msg.setDistance(resultSet.getString("distance"));
msg.setMessage(resultSet.getString("message"));
msgList.add(msg);
}
// 关闭资源
resultSet.close();
preparedStatement.close();
return msgList;
}
@Override
public void close() throws Exception {
connection.close();
}
}
运行测试方法:
@Test
public void getMesage() throws Exception {
List<Msg> message = chatMessageService.getMessage("2022-01-29", "13514684105", "13647128512");
for (Msg msg : message) {
System.out.println(msg);
}
}
4. 测试下sql
select
*
from
"MOMO_CHAT"."MSG"
where
substr("msg_time", 0, 10) = '2022-01-29'
and "sender_account" = '13514684105'
and "receiver_account" = '13647128512';
标签:JDBC,varchar,sender,Phoenix,resultSet,开发,receiver,msg,C1 来源: https://blog.csdn.net/qq_37362891/article/details/122753293