[HUDI-764] [HUDI-765] ORC reader writer Implementation (#2999)

Co-authored-by: Qingyun (Teresa) Kang <kteresa@uber.com>

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/config/HoodieStorageConfig.java

@@ -39,10 +39,21 @@ public class HoodieStorageConfig extends DefaultHoodieConfig {
   public static final String DEFAULT_PARQUET_BLOCK_SIZE_BYTES = DEFAULT_PARQUET_FILE_MAX_BYTES;
   public static final String PARQUET_PAGE_SIZE_BYTES = "hoodie.parquet.page.size";
   public static final String DEFAULT_PARQUET_PAGE_SIZE_BYTES = String.valueOf(1 * 1024 * 1024);
+
   public static final String HFILE_FILE_MAX_BYTES = "hoodie.hfile.max.file.size";
   public static final String HFILE_BLOCK_SIZE_BYTES = "hoodie.hfile.block.size";
   public static final String DEFAULT_HFILE_BLOCK_SIZE_BYTES = String.valueOf(1 * 1024 * 1024);
   public static final String DEFAULT_HFILE_FILE_MAX_BYTES = String.valueOf(120 * 1024 * 1024);
+
+  public static final String ORC_FILE_MAX_BYTES = "hoodie.orc.max.file.size";
+  public static final String DEFAULT_ORC_FILE_MAX_BYTES = String.valueOf(120 * 1024 * 1024);
+  // size of the memory buffer in bytes for writing
+  public static final String ORC_STRIPE_SIZE = "hoodie.orc.stripe.size";
+  public static final String DEFAULT_ORC_STRIPE_SIZE = String.valueOf(64 * 1024 * 1024);
+  // file system block size
+  public static final String ORC_BLOCK_SIZE = "hoodie.orc.block.size";
+  public static final String DEFAULT_ORC_BLOCK_SIZE = DEFAULT_ORC_FILE_MAX_BYTES;
+
   // used to size log files
   public static final String LOGFILE_SIZE_MAX_BYTES = "hoodie.logfile.max.size";
   public static final String DEFAULT_LOGFILE_SIZE_MAX_BYTES = String.valueOf(1024 * 1024 * 1024); // 1 GB
@@ -54,9 +65,11 @@ public class HoodieStorageConfig extends DefaultHoodieConfig {
   public static final String DEFAULT_STREAM_COMPRESSION_RATIO = String.valueOf(0.1);
   public static final String PARQUET_COMPRESSION_CODEC = "hoodie.parquet.compression.codec";
   public static final String HFILE_COMPRESSION_ALGORITHM = "hoodie.hfile.compression.algorithm";
+  public static final String ORC_COMPRESSION_CODEC = "hoodie.orc.compression.codec";
   // Default compression codec for parquet
   public static final String DEFAULT_PARQUET_COMPRESSION_CODEC = "gzip";
   public static final String DEFAULT_HFILE_COMPRESSION_ALGORITHM = "GZ";
+  public static final String DEFAULT_ORC_COMPRESSION_CODEC = "ZLIB";
   public static final String LOGFILE_TO_PARQUET_COMPRESSION_RATIO = "hoodie.logfile.to.parquet.compression.ratio";
   // Default compression ratio for log file to parquet, general 3x
   public static final String DEFAULT_LOGFILE_TO_PARQUET_COMPRESSION_RATIO = String.valueOf(0.35);
@@ -140,6 +153,26 @@ public class HoodieStorageConfig extends DefaultHoodieConfig {
       return this;
     }
 
+    public Builder orcMaxFileSize(long maxFileSize) {
+      props.setProperty(ORC_FILE_MAX_BYTES, String.valueOf(maxFileSize));
+      return this;
+    }
+
+    public Builder orcStripeSize(int orcStripeSize) {
+      props.setProperty(ORC_STRIPE_SIZE, String.valueOf(orcStripeSize));
+      return this;
+    }
+
+    public Builder orcBlockSize(int orcBlockSize) {
+      props.setProperty(ORC_BLOCK_SIZE, String.valueOf(orcBlockSize));
+      return this;
+    }
+
+    public Builder orcCompressionCodec(String orcCompressionCodec) {
+      props.setProperty(ORC_COMPRESSION_CODEC, orcCompressionCodec);
+      return this;
+    }
+
     public HoodieStorageConfig build() {
       HoodieStorageConfig config = new HoodieStorageConfig(props);
       setDefaultOnCondition(props, !props.containsKey(PARQUET_FILE_MAX_BYTES), PARQUET_FILE_MAX_BYTES,
@@ -166,6 +199,15 @@ public class HoodieStorageConfig extends DefaultHoodieConfig {
       setDefaultOnCondition(props, !props.containsKey(HFILE_FILE_MAX_BYTES), HFILE_FILE_MAX_BYTES,
           DEFAULT_HFILE_FILE_MAX_BYTES);
 
+      setDefaultOnCondition(props, !props.containsKey(ORC_FILE_MAX_BYTES), ORC_FILE_MAX_BYTES,
+          DEFAULT_ORC_FILE_MAX_BYTES);
+      setDefaultOnCondition(props, !props.containsKey(ORC_STRIPE_SIZE), ORC_STRIPE_SIZE,
+          DEFAULT_ORC_STRIPE_SIZE);
+      setDefaultOnCondition(props, !props.containsKey(ORC_BLOCK_SIZE), ORC_BLOCK_SIZE,
+          DEFAULT_ORC_BLOCK_SIZE);
+      setDefaultOnCondition(props, !props.containsKey(ORC_COMPRESSION_CODEC), ORC_COMPRESSION_CODEC,
+          DEFAULT_ORC_COMPRESSION_CODEC);
+
       return config;
     }
   }

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/config/HoodieWriteConfig.java

@@ -42,6 +42,7 @@ import org.apache.hudi.metrics.MetricsReporterType;
 import org.apache.hudi.metrics.datadog.DatadogHttpClient.ApiSite;
 import org.apache.hudi.table.action.compact.CompactionTriggerStrategy;
 import org.apache.hudi.table.action.compact.strategy.CompactionStrategy;
+import org.apache.orc.CompressionKind;
 import org.apache.parquet.hadoop.metadata.CompressionCodecName;
 
 import javax.annotation.concurrent.Immutable;
@@ -784,6 +785,22 @@ public class HoodieWriteConfig extends DefaultHoodieConfig {
     return Compression.Algorithm.valueOf(props.getProperty(HoodieStorageConfig.HFILE_COMPRESSION_ALGORITHM));
   }
 
+  public long getOrcMaxFileSize() {
+    return Long.parseLong(props.getProperty(HoodieStorageConfig.ORC_FILE_MAX_BYTES));
+  }
+
+  public int getOrcStripeSize() {
+    return Integer.parseInt(props.getProperty(HoodieStorageConfig.ORC_STRIPE_SIZE));
+  }
+
+  public int getOrcBlockSize() {
+    return Integer.parseInt(props.getProperty(HoodieStorageConfig.ORC_BLOCK_SIZE));
+  }
+
+  public CompressionKind getOrcCompressionCodec() {
+    return CompressionKind.valueOf(props.getProperty(HoodieStorageConfig.ORC_COMPRESSION_CODEC));
+  }
+
   /**
    * metrics properties.
    */

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/io/storage/HoodieFileWriter.java

@@ -18,6 +18,9 @@
 
 package org.apache.hudi.io.storage;
 
+import java.util.concurrent.atomic.AtomicLong;
+import org.apache.avro.generic.GenericRecord;
+import org.apache.hudi.avro.HoodieAvroUtils;
 import org.apache.hudi.common.model.HoodieRecord;
 
 import org.apache.avro.generic.IndexedRecord;
@@ -35,4 +38,11 @@ public interface HoodieFileWriter<R extends IndexedRecord> {
   void writeAvro(String key, R oldRecord) throws IOException;
 
   long getBytesWritten();
+
+  default void prepRecordWithMetadata(R avroRecord, HoodieRecord record, String instantTime, Integer partitionId, AtomicLong recordIndex, String fileName) {
+    String seqId = HoodieRecord.generateSequenceId(instantTime, partitionId, recordIndex.getAndIncrement());
+    HoodieAvroUtils.addHoodieKeyToRecord((GenericRecord) avroRecord, record.getRecordKey(), record.getPartitionPath(), fileName);
+    HoodieAvroUtils.addCommitMetadataToRecord((GenericRecord) avroRecord, instantTime, seqId);
+    return;
+  }
 }

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/io/storage/HoodieFileWriterFactory.java

@@ -34,6 +34,7 @@ import org.apache.parquet.avro.AvroSchemaConverter;
 
 import java.io.IOException;
 
+import static org.apache.hudi.common.model.HoodieFileFormat.ORC;
 import static org.apache.hudi.common.model.HoodieFileFormat.PARQUET;
 import static org.apache.hudi.common.model.HoodieFileFormat.HFILE;
 
@@ -49,6 +50,9 @@ public class HoodieFileWriterFactory {
     if (HFILE.getFileExtension().equals(extension)) {
       return newHFileFileWriter(instantTime, path, config, schema, hoodieTable, taskContextSupplier);
     }
+    if (ORC.getFileExtension().equals(extension)) {
+      return newOrcFileWriter(instantTime, path, config, schema, hoodieTable, taskContextSupplier);
+    }
     throw new UnsupportedOperationException(extension + " format not supported yet.");
   }
 
@@ -77,6 +81,15 @@ public class HoodieFileWriterFactory {
     return new HoodieHFileWriter<>(instantTime, path, hfileConfig, schema, taskContextSupplier);
   }
 
+  private static <T extends HoodieRecordPayload, R extends IndexedRecord> HoodieFileWriter<R> newOrcFileWriter(
+      String instantTime, Path path, HoodieWriteConfig config, Schema schema, HoodieTable hoodieTable,
+      TaskContextSupplier taskContextSupplier) throws IOException {
+    BloomFilter filter = createBloomFilter(config);
+    HoodieOrcConfig orcConfig = new HoodieOrcConfig(hoodieTable.getHadoopConf(), config.getOrcCompressionCodec(),
+        config.getOrcStripeSize(), config.getOrcBlockSize(), config.getOrcMaxFileSize(), filter);
+    return new HoodieOrcWriter<>(instantTime, path, orcConfig, schema, taskContextSupplier);
+  }
+
   private static BloomFilter createBloomFilter(HoodieWriteConfig config) {
     return BloomFilterFactory.createBloomFilter(config.getBloomFilterNumEntries(), config.getBloomFilterFPP(),
             config.getDynamicBloomFilterMaxNumEntries(),

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/io/storage/HoodieHFileWriter.java

@@ -99,13 +99,9 @@ public class HoodieHFileWriter<T extends HoodieRecordPayload, R extends IndexedR
 
   @Override
   public void writeAvroWithMetadata(R avroRecord, HoodieRecord record) throws IOException {
-    String seqId =
-        HoodieRecord.generateSequenceId(instantTime, taskContextSupplier.getPartitionIdSupplier().get(), recordIndex.getAndIncrement());
-    HoodieAvroUtils.addHoodieKeyToRecord((GenericRecord) avroRecord, record.getRecordKey(), record.getPartitionPath(),
-        file.getName());
-    HoodieAvroUtils.addCommitMetadataToRecord((GenericRecord) avroRecord, instantTime, seqId);
-
-    writeAvro(record.getRecordKey(), (IndexedRecord)avroRecord);
+    prepRecordWithMetadata(avroRecord, record, instantTime,
+        taskContextSupplier.getPartitionIdSupplier().get(), recordIndex, file.getName());
+    writeAvro(record.getRecordKey(), (IndexedRecord) avroRecord);
   }
 
   @Override

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/io/storage/HoodieOrcConfig.java

@@ -0,0 +1,72 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hudi.io.storage;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hudi.common.bloom.BloomFilter;
+import org.apache.orc.CompressionKind;
+
+public class HoodieOrcConfig {
+  static final String AVRO_SCHEMA_METADATA_KEY = "orc.avro.schema";
+
+  private final CompressionKind compressionKind;
+  private final int stripeSize;
+  private final int blockSize;
+  private final long maxFileSize;
+  private final Configuration hadoopConf;
+  private final BloomFilter bloomFilter;
+
+  public HoodieOrcConfig(Configuration hadoopConf, CompressionKind compressionKind, int stripeSize,
+      int blockSize, long maxFileSize, BloomFilter bloomFilter) {
+    this.hadoopConf = hadoopConf;
+    this.compressionKind = compressionKind;
+    this.stripeSize = stripeSize;
+    this.blockSize = blockSize;
+    this.maxFileSize = maxFileSize;
+    this.bloomFilter = bloomFilter;
+  }
+
+  public Configuration getHadoopConf() {
+    return hadoopConf;
+  }
+
+  public CompressionKind getCompressionKind() {
+    return compressionKind;
+  }
+
+  public int getStripeSize() {
+    return stripeSize;
+  }
+
+  public int getBlockSize() {
+    return blockSize;
+  }
+
+  public long getMaxFileSize() {
+    return maxFileSize;
+  }
+
+  public boolean useBloomFilter() {
+    return bloomFilter != null;
+  }
+
+  public BloomFilter getBloomFilter() {
+    return bloomFilter;
+  }
+}

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/io/storage/HoodieOrcWriter.java

@@ -0,0 +1,172 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hudi.io.storage;
+
+import static org.apache.hudi.avro.HoodieAvroWriteSupport.HOODIE_AVRO_BLOOM_FILTER_METADATA_KEY;
+import static org.apache.hudi.avro.HoodieAvroWriteSupport.HOODIE_BLOOM_FILTER_TYPE_CODE;
+import static org.apache.hudi.avro.HoodieAvroWriteSupport.HOODIE_MAX_RECORD_KEY_FOOTER;
+import static org.apache.hudi.avro.HoodieAvroWriteSupport.HOODIE_MIN_RECORD_KEY_FOOTER;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicLong;
+import org.apache.avro.Schema;
+import org.apache.avro.generic.GenericRecord;
+import org.apache.avro.generic.IndexedRecord;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.Path;
+import org.apache.orc.storage.ql.exec.vector.ColumnVector;
+import org.apache.orc.storage.ql.exec.vector.VectorizedRowBatch;
+import org.apache.hudi.common.bloom.BloomFilter;
+import org.apache.hudi.common.bloom.HoodieDynamicBoundedBloomFilter;
+import org.apache.orc.OrcFile;
+import org.apache.orc.TypeDescription;
+import org.apache.orc.Writer;
+import org.apache.hudi.common.engine.TaskContextSupplier;
+import org.apache.hudi.common.fs.FSUtils;
+import org.apache.hudi.common.fs.HoodieWrapperFileSystem;
+import org.apache.hudi.common.model.HoodieRecord;
+import org.apache.hudi.common.model.HoodieRecordPayload;
+import org.apache.hudi.common.util.AvroOrcUtils;
+
+public class HoodieOrcWriter<T extends HoodieRecordPayload, R extends IndexedRecord>
+    implements HoodieFileWriter<R> {
+  private static final AtomicLong RECORD_INDEX = new AtomicLong(1);
+
+  private final long maxFileSize;
+  private final Schema avroSchema;
+  private final List<TypeDescription> fieldTypes;
+  private final List<String> fieldNames;
+  private final VectorizedRowBatch batch;
+  private final Writer writer;
+
+  private final Path file;
+  private final HoodieWrapperFileSystem fs;
+  private final String instantTime;
+  private final TaskContextSupplier taskContextSupplier;
+
+  private HoodieOrcConfig orcConfig;
+  private String minRecordKey;
+  private String maxRecordKey;
+
+  public HoodieOrcWriter(String instantTime, Path file, HoodieOrcConfig config, Schema schema,
+      TaskContextSupplier taskContextSupplier) throws IOException {
+
+    Configuration conf = FSUtils.registerFileSystem(file, config.getHadoopConf());
+    this.file = HoodieWrapperFileSystem.convertToHoodiePath(file, conf);
+    this.fs = (HoodieWrapperFileSystem) this.file.getFileSystem(conf);
+    this.instantTime = instantTime;
+    this.taskContextSupplier = taskContextSupplier;
+
+    this.avroSchema = schema;
+    final TypeDescription orcSchema = AvroOrcUtils.createOrcSchema(avroSchema);
+    this.fieldTypes = orcSchema.getChildren();
+    this.fieldNames = orcSchema.getFieldNames();
+    this.maxFileSize = config.getMaxFileSize();
+    this.batch = orcSchema.createRowBatch();
+    OrcFile.WriterOptions writerOptions = OrcFile.writerOptions(conf)
+        .blockSize(config.getBlockSize())
+        .stripeSize(config.getStripeSize())
+        .compress(config.getCompressionKind())
+        .bufferSize(config.getBlockSize())
+        .fileSystem(fs)
+        .setSchema(orcSchema);
+    this.writer = OrcFile.createWriter(this.file, writerOptions);
+    this.orcConfig = config;
+  }
+
+  @Override
+  public void writeAvroWithMetadata(R avroRecord, HoodieRecord record) throws IOException {
+    prepRecordWithMetadata(avroRecord, record, instantTime,
+        taskContextSupplier.getPartitionIdSupplier().get(), RECORD_INDEX, file.getName());
+    writeAvro(record.getRecordKey(), avroRecord);
+  }
+
+  @Override
+  public boolean canWrite() {
+    return fs.getBytesWritten(file) < maxFileSize;
+  }
+
+  @Override
+  public void writeAvro(String recordKey, IndexedRecord object) throws IOException {
+    for (int col = 0; col < batch.numCols; col++) {
+      ColumnVector colVector = batch.cols[col];
+      final String thisField = fieldNames.get(col);
+      final TypeDescription type = fieldTypes.get(col);
+
+      Object fieldValue = ((GenericRecord) object).get(thisField);
+      Schema.Field avroField = avroSchema.getField(thisField);
+      AvroOrcUtils.addToVector(type, colVector, avroField.schema(), fieldValue, batch.size);
+    }
+
+    batch.size++;
+
+    // Batch size corresponds to the number of written rows out of 1024 total rows (by default)
+    // in the row batch, add the batch to file once all rows are filled and reset.
+    if (batch.size == batch.getMaxSize()) {
+      writer.addRowBatch(batch);
+      batch.reset();
+      batch.size = 0;
+    }
+
+    if (orcConfig.useBloomFilter()) {
+      orcConfig.getBloomFilter().add(recordKey);
+      if (minRecordKey != null) {
+        minRecordKey = minRecordKey.compareTo(recordKey) <= 0 ? minRecordKey : recordKey;
+      } else {
+        minRecordKey = recordKey;
+      }
+
+      if (maxRecordKey != null) {
+        maxRecordKey = maxRecordKey.compareTo(recordKey) >= 0 ? maxRecordKey : recordKey;
+      } else {
+        maxRecordKey = recordKey;
+      }
+    }
+  }
+
+  @Override
+  public void close() throws IOException {
+    if (batch.size != 0) {
+      writer.addRowBatch(batch);
+      batch.reset();
+    }
+
+    if (orcConfig.useBloomFilter()) {
+      final BloomFilter bloomFilter = orcConfig.getBloomFilter();
+      writer.addUserMetadata(HOODIE_AVRO_BLOOM_FILTER_METADATA_KEY, ByteBuffer.wrap(bloomFilter.serializeToString().getBytes()));
+      if (minRecordKey != null && maxRecordKey != null) {
+        writer.addUserMetadata(HOODIE_MIN_RECORD_KEY_FOOTER, ByteBuffer.wrap(minRecordKey.getBytes()));
+        writer.addUserMetadata(HOODIE_MAX_RECORD_KEY_FOOTER, ByteBuffer.wrap(maxRecordKey.getBytes()));
+      }
+      if (bloomFilter.getBloomFilterTypeCode().name().contains(HoodieDynamicBoundedBloomFilter.TYPE_CODE_PREFIX)) {
+        writer.addUserMetadata(HOODIE_BLOOM_FILTER_TYPE_CODE, ByteBuffer.wrap(bloomFilter.getBloomFilterTypeCode().name().getBytes()));
+      }
+    }
+    writer.addUserMetadata(HoodieOrcConfig.AVRO_SCHEMA_METADATA_KEY, ByteBuffer.wrap(avroSchema.toString().getBytes()));
+
+    writer.close();
+  }
+
+  @Override
+  public long getBytesWritten() {
+    return fs.getBytesWritten(file);
+  }
+}

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/io/storage/HoodieParquetWriter.java

@@ -18,7 +18,6 @@
 
 package org.apache.hudi.io.storage;
 
-import org.apache.hudi.avro.HoodieAvroUtils;
 import org.apache.hudi.avro.HoodieAvroWriteSupport;
 import org.apache.hudi.common.engine.TaskContextSupplier;
 import org.apache.hudi.common.fs.FSUtils;
@@ -27,7 +26,6 @@ import org.apache.hudi.common.model.HoodieRecord;
 import org.apache.hudi.common.model.HoodieRecordPayload;
 
 import org.apache.avro.Schema;
-import org.apache.avro.generic.GenericRecord;
 import org.apache.avro.generic.IndexedRecord;
 import org.apache.hadoop.fs.Path;
 import org.apache.parquet.hadoop.ParquetFileWriter;
@@ -75,11 +73,8 @@ public class HoodieParquetWriter<T extends HoodieRecordPayload, R extends Indexe
 
   @Override
   public void writeAvroWithMetadata(R avroRecord, HoodieRecord record) throws IOException {
-    String seqId =
-        HoodieRecord.generateSequenceId(instantTime, taskContextSupplier.getPartitionIdSupplier().get(), recordIndex.getAndIncrement());
-    HoodieAvroUtils.addHoodieKeyToRecord((GenericRecord) avroRecord, record.getRecordKey(), record.getPartitionPath(),
-        file.getName());
-    HoodieAvroUtils.addCommitMetadataToRecord((GenericRecord) avroRecord, instantTime, seqId);
+    prepRecordWithMetadata(avroRecord, record, instantTime,
+        taskContextSupplier.getPartitionIdSupplier().get(), recordIndex, file.getName());
     super.write(avroRecord);
     writeSupport.add(record.getRecordKey());
   }

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/table/HoodieTable.java

@@ -656,6 +656,7 @@ public abstract class HoodieTable<T extends HoodieRecordPayload, I, K, O> implem
   public HoodieLogBlockType getLogDataBlockFormat() {
     switch (getBaseFileFormat()) {
       case PARQUET:
+      case ORC:
         return HoodieLogBlockType.AVRO_DATA_BLOCK;
       case HFILE:
         return HoodieLogBlockType.HFILE_DATA_BLOCK;