this.aggPositionOffsets = new int[metrics.length];
int currAggSize = 0;
for (int i = 0; i < metrics.length; i++) {
final AggregatorFactory agg = metrics[i];
aggs[i] = agg.factorizeBuffered(
new ColumnSelectorFactory()
{
@Override
public LongColumnSelector makeLongColumnSelector(String columnName)
{
if(columnName.equals(Column.TIME_COLUMN_NAME)){