Examples with DataWritableReadSupport org.apache.hadoop.hive.ql.io.parquet.read.DataWritableReadSupport used on opensource projects

Example 1 with DataWritableReadSupport

use of org.apache.hadoop.hive.ql.io.parquet.read.DataWritableReadSupport in project hive by apache.

the class ParquetRecordReaderBase method getSplit.

/**
   * gets a ParquetInputSplit corresponding to a split given by Hive
   *
   * @param oldSplit The split given by Hive
   * @param conf The JobConf of the Hive job
   * @return a ParquetInputSplit corresponding to the oldSplit
   * @throws IOException if the config cannot be enhanced or if the footer cannot be read from the file
   */
@SuppressWarnings("deprecation")
protected ParquetInputSplit getSplit(final org.apache.hadoop.mapred.InputSplit oldSplit, final JobConf conf) throws IOException {
    ParquetInputSplit split;
    if (oldSplit == null) {
        return null;
    }
    if (oldSplit instanceof FileSplit) {
        final Path finalPath = ((FileSplit) oldSplit).getPath();
        jobConf = projectionPusher.pushProjectionsAndFilters(conf, finalPath.getParent());
        // TODO enable MetadataFilter by using readFooter(Configuration configuration, Path file,
        // MetadataFilter filter) API
        final ParquetMetadata parquetMetadata = ParquetFileReader.readFooter(jobConf, finalPath);
        final List<BlockMetaData> blocks = parquetMetadata.getBlocks();
        final FileMetaData fileMetaData = parquetMetadata.getFileMetaData();
        final ReadSupport.ReadContext readContext = new DataWritableReadSupport().init(new InitContext(jobConf, null, fileMetaData.getSchema()));
        // Compute stats
        for (BlockMetaData bmd : blocks) {
            serDeStats.setRowCount(serDeStats.getRowCount() + bmd.getRowCount());
            serDeStats.setRawDataSize(serDeStats.getRawDataSize() + bmd.getTotalByteSize());
        }
        schemaSize = MessageTypeParser.parseMessageType(readContext.getReadSupportMetadata().get(DataWritableReadSupport.HIVE_TABLE_AS_PARQUET_SCHEMA)).getFieldCount();
        final List<BlockMetaData> splitGroup = new ArrayList<BlockMetaData>();
        final long splitStart = ((FileSplit) oldSplit).getStart();
        final long splitLength = ((FileSplit) oldSplit).getLength();
        for (final BlockMetaData block : blocks) {
            final long firstDataPage = block.getColumns().get(0).getFirstDataPageOffset();
            if (firstDataPage >= splitStart && firstDataPage < splitStart + splitLength) {
                splitGroup.add(block);
            }
        }
        if (splitGroup.isEmpty()) {
            LOG.warn("Skipping split, could not find row group in: " + oldSplit);
            return null;
        }
        FilterCompat.Filter filter = setFilter(jobConf, fileMetaData.getSchema());
        if (filter != null) {
            filtedBlocks = RowGroupFilter.filterRowGroups(filter, splitGroup, fileMetaData.getSchema());
            if (filtedBlocks.isEmpty()) {
                LOG.debug("All row groups are dropped due to filter predicates");
                return null;
            }
            long droppedBlocks = splitGroup.size() - filtedBlocks.size();
            if (droppedBlocks > 0) {
                LOG.debug("Dropping " + droppedBlocks + " row groups that do not pass filter predicate");
            }
        } else {
            filtedBlocks = splitGroup;
        }
        split = new ParquetInputSplit(finalPath, splitStart, splitLength, oldSplit.getLocations(), filtedBlocks, readContext.getRequestedSchema().toString(), fileMetaData.getSchema().toString(), fileMetaData.getKeyValueMetaData(), readContext.getReadSupportMetadata());
        return split;
    } else {
        throw new IllegalArgumentException("Unknown split type: " + oldSplit);
    }
}