/** * Variant of {@link #trimFields(RelNode, ImmutableBitSet, Set)} for {@link * org.apache.hadoop.hive.ql.optimizer.calcite.reloperators.HiveMultiJoin}. */ public TrimResult trimFields( HiveMultiJoin join, ImmutableBitSet fieldsUsed, Set<RelDataTypeField> extraFields) { final int fieldCount = join.getRowType().getFieldCount(); final RexNode conditionExpr = join.getCondition(); // Add in fields used in the condition. final Set<RelDataTypeField> combinedInputExtraFields = new LinkedHashSet<RelDataTypeField>(extraFields); RelOptUtil.InputFinder inputFinder = new RelOptUtil.InputFinder(combinedInputExtraFields); inputFinder.inputBitSet.addAll(fieldsUsed); conditionExpr.accept(inputFinder); final ImmutableBitSet fieldsUsedPlus = inputFinder.inputBitSet.build(); int inputStartPos = 0; int changeCount = 0; int newFieldCount = 0; List<RelNode> newInputs = new ArrayList<RelNode>(); List<Mapping> inputMappings = new ArrayList<Mapping>(); for (RelNode input : join.getInputs()) { final RelDataType inputRowType = input.getRowType(); final int inputFieldCount = inputRowType.getFieldCount(); // Compute required mapping. ImmutableBitSet.Builder inputFieldsUsed = ImmutableBitSet.builder(); for (int bit : fieldsUsedPlus) { if (bit >= inputStartPos && bit < inputStartPos + inputFieldCount) { inputFieldsUsed.set(bit - inputStartPos); } } Set<RelDataTypeField> inputExtraFields = Collections.<RelDataTypeField>emptySet(); TrimResult trimResult = trimChild(join, input, inputFieldsUsed.build(), inputExtraFields); newInputs.add(trimResult.left); if (trimResult.left != input) { ++changeCount; } final Mapping inputMapping = trimResult.right; inputMappings.add(inputMapping); // Move offset to point to start of next input. inputStartPos += inputFieldCount; newFieldCount += inputMapping.getTargetCount(); } Mapping mapping = Mappings.create(MappingType.INVERSE_SURJECTION, fieldCount, newFieldCount); int offset = 0; int newOffset = 0; for (int i = 0; i < inputMappings.size(); i++) { Mapping inputMapping = inputMappings.get(i); for (IntPair pair : inputMapping) { mapping.set(pair.source + offset, pair.target + newOffset); } offset += inputMapping.getSourceCount(); newOffset += inputMapping.getTargetCount(); } if (changeCount == 0 && mapping.isIdentity()) { return new TrimResult(join, Mappings.createIdentity(fieldCount)); } // Build new join. final RexVisitor<RexNode> shuttle = new RexPermuteInputsShuttle(mapping, newInputs.toArray(new RelNode[newInputs.size()])); RexNode newConditionExpr = conditionExpr.accept(shuttle); final RelDataType newRowType = RelOptUtil.permute(join.getCluster().getTypeFactory(), join.getRowType(), mapping); final RelNode newJoin = new HiveMultiJoin( join.getCluster(), newInputs, newConditionExpr, newRowType, join.getJoinInputs(), join.getJoinTypes(), join.getJoinFilters()); return new TrimResult(newJoin, mapping); }