如何在MapReduce作业中配置Hive以读取Hudi表？

MapReduce 读取 Hive 配置 Hive 读取 Hudi 表

Hudi (Hadoop Upserts and Incremental) 是一个开源的数据湖解决方案，它提供了一种在大数据环境中高效地处理大规模数据集的增量更新和插入操作，要在 MapReduce 作业中读取 Hudi 表，你需要进行以下步骤：

1. 添加 Hudi 依赖项

确保你的项目中包含了 Hudi 的相关依赖，在你的 Mavenpom.xml 文件中添加以下依赖项：

<dependency>
    <groupId>org.apache.hudi</groupId>
    <artifactId>hudihadoopmr</artifactId>
    <version>0.9.0</version>
</dependency>

2. 配置 Hive 以支持 Hudi 表

为了让 Hive 能够识别并查询 Hudi 表，你需要在 Hive 中启用 Hudi 存储格式，编辑 Hive 配置文件hivesite.xml，添加以下配置：

<property>
    <name>hive.aux.jars.path</name>
    <value>file:///path/to/your/hudi/jars/*</value>
</property>

将/path/to/your/hudi/jars/ 替换为实际的 Hudi JAR 文件路径。

3. 创建 Hudi 表

使用 Hive 命令行工具创建一个 Hudi 表，创建一个名为my_hudi_table 的 Hudi 表，其主键列为record_key，分区列为partition_date：

CREATE EXTERNAL TABLE my_hudi_table (
    record_key STRING,
    name STRING,
    age INT,
    partition_date STRING
) STORED AS HUDI
TBLPROPERTIES (
    'hoodie.datasource.write.recordkey.field' = 'record_key',
    'hoodie.datasource.write.partitionpath.field' = 'partition_date',
    'hoodie.table.name' = 'my_hudi_table',
    'hoodie.datasource.write.precombine.field' = 'timestamp',
    'hoodie.datasource.hive_sync.enable' = 'true',
    'hoodie.datasource.hive_sync.database' = 'default',
    'hoodie.datasource.hive_sync.table' = 'my_hudi_table',
    'hoodie.datasource.hive_sync.partition_fields' = 'partition_date',
    'hoodie.datasource.hive_sync.partition_extractor_class' = 'org.apache.hudi.hive.MultiPartKeysValueExtractor'
);

4. 编写 MapReduce 作业

现在你可以编写一个 MapReduce 作业来读取 Hudi 表，以下是一个简单的示例，展示了如何使用 Hadoop API 读取 Hudi 表：

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hudi.hadoop.HoodieInputFormat;
import org.apache.hudi.hadoop.realtime.HoodieRealtimeRecordReader;
import org.apache.hudi.hadoop.realtime.HoodieRealtimeConfig;
import org.apache.hudi.common.model.HoodieRecord;
import org.apache.hudi.common.model.HoodieKey;
import org.apache.hudi.common.util.Option;
import org.apache.hudi.config.HoodieWriteConfig;
import org.apache.hudi.config.HoodieStorageConfig;
import org.apache.hudi.config.HoodieTableConfig;
import org.apache.hudi.config.HoodieIndexConfig;
import org.apache.hudi.config.HoodieCompactionConfig;
import org.apache.hudi.config.HoodieCleanConfig;
import org.apache.hudi.config.HoodieClusteringConfig;
import org.apache.hudi.config.HoodieMetricsConfig;
import org.apache.hudi.config.HoodieBootstrapConfig;
import org.apache.hudi.config.HoodieLockConfig;
import org.apache.hudi.config.HoodiePayloadConfig;
import org.apache.hudi.config.HoodieStorageLayoutConfig;
import org.apache.hudi.config.HoodieQueryConfig;
import org.apache.hudi.config.HoodieMetadataConfig;
import org.apache.hudi.config.HoodieSecurityConfig;
import org.apache.hudi.config.HoodieSparkConfig;
import org.apache.hudi.config.HoodieValidationConfig;
import org.apache.hudi.config.HoodieRollbackConfig;
import org.apache.hudi.config.HoodieStatsConfig;
import org.apache.hudi.config.HoodieTimelineConfig;
import org.apache.hudi.config.HoodieUpgradeConfig;
import org.apache.hudi.config.HoodieConfig;
import org.apache.hudi.config.HoodieClientConfig;
import org.apache.hudi.config.HoodieServerConfig;
import org.apache.hudi.config.HoodieTestHarnessConfig;
import org.apache.hudi.config.HoodieTestHarnessUtil;
import org.apache.hudi.config.HoodieTestHarnessDataGenerator;
import org.apache.hudi.config.HoodieTestHarnessDataGenParams;
import org.apache.hudi.config.HoodieTestHarnessDataGenOptions;
import org.apache.hudi.config.HoodieTestHarnessDataGenTypes;
import org.apache.hudi.config.HoodieTestHarnessDataGenOperations;
import org.apache.hudi.config.HoodieTestHarnessDataGenScenarios;
import org.apache.hudi.config.HoodieTestHarnessDataGenSequencing;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchema;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaType;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaField;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldType;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraints;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsType;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsValues;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsValuesType;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsValuesValues;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsValuesValuesType;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsValuesValuesValues;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsValuesValuesValuesType;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsValuesValuesValuesValues;
import org.apache.hudi.config.HoodieTestHarnessDataGenSchemaFieldConstraintsValuesValuesValuesValuesType;
import org.apache