如何从java查询druid数据?

请结帐 DruidDry . 这是一个基于java的实用程序库,用于查询druid。

Druid dry支持使用Java API编写查询json和查询代理节点。目前,它不支持几个复杂的JSON,也不支持摄入规范。但是,它确实支持最常见的操作,如选择、扫描、分组等。

您的项目需要在Java 8或更高版本上运行,才能使用druid干式客户端。

这里有一个简单的 Spring Boot Java应用程序 哪些查询 德鲁伊 数据使用 并打印查询中的第一行。

假设Druid在本地运行,并且表名中已有数据“ druid_表 “其中有一列

FlinkDruidApplication。Java语言

@SpringBootApplication
public class FlinkDruidApplication {

    public static void main(String[] args) {
        SpringApplication.run(FlinkDruidApplication.class, args);
        Logger log = LoggerFactory.getLogger("FlinkDruidApplication");
        ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
        DataSet<Row> dbData =
                env.createInput(
                        JDBCInputFormat
                                .buildJDBCInputFormat()
                                .setDrivername("org.apache.calcite.avatica.remote.Driver")
                                .setDBUrl("jdbc:avatica:remote:url=http://localhost:8082/druid/v2/sql/avatica/")
                                .setUsername("null")
                                .setPassword("null")
                                .setQuery(
                                        "SELECT sourceIP FROM druid_table"
                                )
                                .setRowTypeInfo((RowTypeInfo) Types.ROW(Types.STRING))
                                .finish()
                );

        try {

            log.info("Printing first IP :: {} " + dbData.collect().iterator().next());
        } catch (Exception e) {
            log.error(e.getMessage());
        }


    }

}

pom。xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://maven.apache.org/POM/4.0.0"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.shashank</groupId>
    <artifactId>FlinkDruid</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>FlinkDruid</name>
    <description>Flink Druid Connection</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.apache.flink/flink-core -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-core</artifactId>
            <version>1.9.0</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.apache.flink/flink-streaming-java -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-java_2.12</artifactId>
            <version>1.9.0</version>
            <scope>provided</scope>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.apache.flink/flink-java -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-java</artifactId>
            <version>1.9.0</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.apache.flink/flink-clients -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-clients_2.12</artifactId>
            <version>1.9.0</version>
        </dependency>

        <!-- https://mvnrepository.com/artifact/org.apache.flink/flink-jdbc -->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-jdbc_2.12</artifactId>
            <version>1.8.1</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.calcite.avatica/avatica-core -->
        <dependency>
            <groupId>org.apache.calcite.avatica</groupId>
            <artifactId>avatica-core</artifactId>
            <version>1.15.0</version>
        </dependency>


    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

您也可以使用 druidry ,基于Java的实用程序库

最简单的事情可能是 Druid SQL over JDBC

下面是如何使用JDBC和Calcite Avatica查询Druid:

添加方解石Avatica

将方解石Avatica添加到POM中:

...
<dependency>
    <groupId>org.apache.calcite.avatica</groupId>
    <artifactId>avatica</artifactId>
    <version>1.21.0</version>
</dependency>
...

示例代码

//  ---------- Set up the Connection -------- //
String url = "jdbc:avatica:remote:url=https://example.com:8888/druid/v2/sql/avatica/";
Properties properties = new Properties();
properties.setProperty("user", "myusername");
properties.setProperty("password", "mypassword");
Connection conn = DriverManager.getConnection(url, properties);

//  --------------- Query Druid ------------- //
String sql = 
    "SELECT page, COUNT(*) AS Edits \n"
    + "FROM \"wikipedia\" \n"
    + "WHERE \"__time\" BETWEEN TIMESTAMP '2015-09-12 00:00:00' AND TIMESTAMP '2015-09-13 00:00:00' \n"
    + "GROUP BY page \n"
    + "ORDER BY Edits DESC \n"
    + "LIMIT 10";
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(sql);

// Do something with the query results here.

请参阅此处的文档: https://druid.apache.org/docs/latest/querying/sql.html#jdbc