public List<Double> averageColumnSizes(Union rel, RelMetadataQuery mq) {
final int fieldCount = rel.getRowType().getFieldCount();
List<List<Double>> inputColumnSizeList = Lists.newArrayList();
for (RelNode input : rel.getInputs()) {
final List<Double> inputSizes = mq.getAverageColumnSizes(input);
if (inputSizes != null) {
inputColumnSizeList.add(inputSizes);
}
}
switch (inputColumnSizeList.size()) {
case 0:
return null; // all were null
case 1:
return inputColumnSizeList.get(0); // all but one were null
}
final ImmutableNullableList.Builder<Double> sizes = ImmutableNullableList.builder();
int nn = 0;
for (int i = 0; i < fieldCount; i++) {
double d = 0d;
int n = 0;
for (List<Double> inputColumnSizes : inputColumnSizeList) {
Double d2 = inputColumnSizes.get(i);
if (d2 != null) {
d += d2;
++n;
++nn;
}
}
sizes.add(n > 0 ? d / n : null);
}
if (nn == 0) {
return null; // all columns are null
}
return sizes.build();
}
public List<Double> averageColumnSizes(Project rel, RelMetadataQuery mq) {
final List<Double> inputColumnSizes = mq.getAverageColumnSizesNotNull(rel.getInput());
final ImmutableNullableList.Builder<Double> sizes = ImmutableNullableList.builder();
for (RexNode project : rel.getProjects()) {
sizes.add(averageRexSize(project, inputColumnSizes));
}
return sizes.build();
}