Examples with TupleReader org.apache.drill.exec.vector.accessor.TupleReader used on opensource projects

Example 26 with TupleReader

use of org.apache.drill.exec.vector.accessor.TupleReader in project drill by apache.

the class MetadataControllerBatch method getColumnStatistics.

private Map<SchemaPath, ColumnStatistics<?>> getColumnStatistics(TupleReader reader, TupleMetadata columnMetadata, Long rowCount) {
    Multimap<String, StatisticsHolder<?>> columnStatistics = ArrayListMultimap.create();
    Map<String, TypeProtos.MinorType> columnTypes = new HashMap<>();
    for (ColumnMetadata column : columnMetadata) {
        if (AnalyzeColumnUtils.isColumnStatisticsField(column.name())) {
            String fieldName = AnalyzeColumnUtils.getColumnName(column.name());
            StatisticsKind<?> statisticsKind = AnalyzeColumnUtils.getStatisticsKind(column.name());
            columnStatistics.put(fieldName, new StatisticsHolder<>(getConvertedColumnValue(reader.column(column.name())), statisticsKind));
            if (statisticsKind.getName().equalsIgnoreCase(ColumnStatisticsKind.MIN_VALUE.getName()) || statisticsKind.getName().equalsIgnoreCase(ColumnStatisticsKind.MAX_VALUE.getName())) {
                columnTypes.putIfAbsent(fieldName, column.type());
            }
        }
    }
    // adds NON_NULL_COUNT to use it during filter pushdown
    if (rowCount != null) {
        Map<String, StatisticsHolder<?>> nullsCountColumnStatistics = new HashMap<>();
        columnStatistics.asMap().forEach((key, value) -> value.stream().filter(statisticsHolder -> statisticsHolder.getStatisticsKind() == ColumnStatisticsKind.NON_NULL_VALUES_COUNT).findAny().map(statisticsHolder -> (Long) statisticsHolder.getStatisticsValue()).ifPresent(nonNullCount -> nullsCountColumnStatistics.put(key, new StatisticsHolder<>(rowCount - nonNullCount, ColumnStatisticsKind.NULLS_COUNT))));
        nullsCountColumnStatistics.forEach(columnStatistics::put);
    }
    Map<SchemaPath, ColumnStatistics<?>> resultingStats = new HashMap<>();
    columnStatistics.asMap().forEach((fieldName, statisticsHolders) -> resultingStats.put(SchemaPath.parseFromString(fieldName), new ColumnStatistics<>(statisticsHolders, columnTypes.get(fieldName))));
    return resultingStats;
}