在 Flink 1.17.2 中使用 Java 读取 StarRocks 数据,可以通过 JDBC 连接器 或 StarRocks 官方提供的 Flink Connector 实现。以下是两种方法的详细步骤:
方法一:使用 Flink JDBC 连接器(兼容 MySQL 协议)
StarRocks 兼容 MySQL 协议,可通过 Flink 的 JDBC 连接器读取数据。在 pom.xml 中添加以下依赖:
<!-- Flink JDBC 连接器 -->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-connector-jdbc</artifactId>
<version>3.1.1-1.17</version>
</dependency>
<!-- MySQL 驱动(兼容 StarRocks) -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.28</version>
</dependency>
编写 Java 代码:
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.api.java.DataSet;
import org.apache.flink.api.java.ExecutionEnvironment;
import org.apache.flink.api.java.typeutils.RowTypeInfo;
import org.apache.flink.connector.jdbc.JdbcInputFormat;
import org.apache.flink.types.Row;
public class ReadStarRocksJDBC {
public static void main(String[] args) throws Exception {
ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
TypeInformation[] fieldTypes = {
Types.STRING,
Types.STRING,
Types.INT
};
RowTypeInfo rowTypeInfo = new RowTypeInfo(fieldTypes);
JdbcInputFormat inputFormat = JdbcInputFormat.buildJdbcInputFormat()
.setDrivername("com.mysql.cj.jdbc.Driver")
.setDBUrl("jdbc:mysql://<starrocks-fe-host>:<port>/<database>")
.setUsername("<username>")
.setPassword("<password>")
.setQuery("SELECT teacher_id, student_id, student_num FROM dwd_student = limit 10")
.setRowTypeInfo(rowTypeInfo)
.finish();
DataSet<Row> dataSet = env.createInput(inputFormat);
dataSet.print();
}
}
输出:
+I[teacher03, abc01, 2]
+I[teacher01, abc01, 3]
方法二:使用 StarRocks Flink Connector(推荐)
StarRocks 提供官方 Connector,支持高效读写。在 pom.xml 中添加以下依赖:
<dependency>
<groupId>com.starrocks.connector</groupId>
<artifactId>flink-connector-starrocks</artifactId>
<version>1.2.8_flink-1.17</version>
</dependency>
通过 Flink SQL 直接注册 StarRocks 表:
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.table.api.bridge.java.StreamTableEnvironment;
public class ReadStarRocksSQL {
public static void main(String[] args) throws Exception {
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env);
String createTableSQL = "CREATE TABLE starrocks_table (\n" +
" id INT,\n" +
" name STRING\n" +
") WITH (\n" +
" 'connector' = 'starrocks',\n" +
" 'jdbc-url' = 'jdbc:mysql://<starrocks-fe-host>:<port>',\n" +
" 'load-url' = '<starrocks-fe-host>:<http-port>',\n" +
" 'database-name' = '<database>',\n" +
" 'table-name' = '<table>',\n" +
" 'username' = '<username>',\n" +
" 'password' = '<password>'\n" +
")";
tableEnv.executeSql(createTableSQL);
tableEnv.executeSql("SELECT * FROM starrocks_table").print();
}
}