How to use

setThreshold

method

in

org.apache.kylin.storage.StorageContext

  private void setConnectionProperties() {
    OptiqConnection conn = (OptiqConnection) optiqContext.getQueryProvider();
    Properties connProps = conn.getProperties();

    String propThreshold = connProps.getProperty(OLAPQuery.PROP_SCAN_THRESHOLD);
    int threshold = Integer.valueOf(propThreshold);
    olapContext.storageContext.setThreshold(threshold);
  }
}

private void setThreshold(Collection<TblColRef> dimensions, List<RowValueDecoder> valueDecoders, StorageContext context) {
  if (RowValueDecoder.hasMemHungryCountDistinct(valueDecoders) == false) {
    return;
  }
  int rowSizeEst = dimensions.size() * 3;
  for (RowValueDecoder decoder : valueDecoders) {
    MeasureDesc[] measures = decoder.getMeasures();
    BitSet projectionIndex = decoder.getProjectionIndex();
    for (int i = projectionIndex.nextSetBit(0); i >= 0; i = projectionIndex.nextSetBit(i + 1)) {
      FunctionDesc func = measures[i].getFunction();
      rowSizeEst += func.getReturnDataType().getSpaceEstimate();
    }
  }
  long rowEst = MEM_BUDGET_PER_QUERY / rowSizeEst;
  context.setThreshold((int) rowEst);
}

@Test(expected = ScanOutOfLimitException.class)
@Ignore
public void testScanOutOfLimit() {
  context.setThreshold(1);
  List<TblColRef> groups = buildGroups();
  List<FunctionDesc> aggregations = buildAggregations();
  search(groups, aggregations, null, context);
}