Examples with TpcdsRecordSet com.facebook.presto.tpcds.TpcdsRecordSet used on opensource projects

Example 1 with TpcdsRecordSet

use of com.facebook.presto.tpcds.TpcdsRecordSet in project presto by prestodb.

the class TableStatisticsRecorder method recordStatistics.

public TableStatisticsData recordStatistics(Table table, double scaleFactor) {
    Session session = Session.getDefaultSession().withScale(scaleFactor).withParallelism(1).withNoSexism(false);
    List<Column> columns = ImmutableList.copyOf(table.getColumns());
    RecordCursor recordCursor = new TpcdsRecordSet(Results.constructResults(table, session), columns).cursor();
    List<ColumnStatisticsRecorder> statisticsRecorders = createStatisticsRecorders(columns);
    long rowCount = 0;
    while (recordCursor.advanceNextPosition()) {
        rowCount++;
        for (int columnId = 0; columnId < columns.size(); columnId++) {
            Comparable<?> value = getPrestoValue(recordCursor, columns, columnId);
            statisticsRecorders.get(columnId).record(value);
        }
    }
    Map<String, ColumnStatisticsData> columnSampleStatistics = IntStream.range(0, columns.size()).boxed().collect(toImmutableMap(i -> columns.get(i).getName(), i -> statisticsRecorders.get(i).getRecording()));
    return new TableStatisticsData(rowCount, columnSampleStatistics);
}