flink实时获取mysql表结构

您可以使用Flink的JDBC连接器来实时获取MySQL表的结构。以下是一个简单的代码示例：

import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.table.api.EnvironmentSettings;
import org.apache.flink.table.api.Table;
import org.apache.flink.table.api.bridge.java.StreamTableEnvironment;
import org.apache.flink.table.sources.tsextractors.ExistingField;
import org.apache.flink.table.sources.wmstrategies.AscendingTimestamps;
import org.apache.flink.table.sources.wmstrategies.BoundedOutOfOrderTimestamps;
import org.apache.flink.table.sources.wmstrategies.PunctuatedWatermarks;
import org.apache.flink.table.sources.wmstrategies.WatermarkStrategy;
import org.apache.flink.types.Row;

public class FlinkMySQLTableSchema {

    public static void main(String[] args) throws Exception {
        // 创建流式执行环境
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        EnvironmentSettings settings = EnvironmentSettings.newInstance().useBlinkPlanner().inStreamingMode().build();
        StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env, settings);

        // 定义MySQL连接器
        tableEnv.executeSql("CREATE TABLE mysql_table (\n" +
                "  id INT,\n" +
                "  name STRING,\n" +
                "  age INT\n" +
                ") WITH (\n" +
                "  'connector' = 'jdbc',\n" +
                "  'url' = 'jdbc:mysql://localhost:3306/test',\n" +
                "  'table-name' = 'your_table_name',\n" +
                "  'username' = 'your_username',\n" +
                "  'password' = 'your_password',\n" +
                "  'lookup.cache.max-rows' = '500'\n" +
                ")");

        // 获取表结构
        Table table = tableEnv.from("mysql_table");
        TypeInformation<Row> typeInfo = table.getSchema().toRowType();
        String[] fieldNames = table.getSchema().getFieldNames();
        TypeInformation<?>[] fieldTypes = table.getSchema().getFieldTypes();

        // 打印表结构
        for (int i = 0; i < fieldNames.length; i++) {
            System.out.println("Field Name: " + fieldNames[i] + ", Field Type: " + fieldTypes[i]);
        }

        // 执行作业
        env.execute();
    }
}

您需要根据实际情况修改代码中的MySQL连接信息和表名，然后运行代码即可实时获取MySQL表的结构。请确保您已经将Flink的相关依赖添加到项目中。