/**
* Returns the type the row which results when two relations are joined.
*
* <p>The resulting row type consists of the system fields (if any), followed by the fields of the
* left type, followed by the fields of the right type. The field name list, if present, overrides
* the original names of the fields.
*
* @param typeFactory Type factory
* @param leftType Type of left input to join
* @param rightType Type of right input to join
* @param fieldNameList If not null, overrides the original names of the fields
* @param systemFieldList List of system fields that will be prefixed to output row type;
* typically empty but must not be null
* @return type of row which results when two relations are joined
*/
public static RelDataType createJoinType(
RelDataTypeFactory typeFactory,
RelDataType leftType,
RelDataType rightType,
List<String> fieldNameList,
List<RelDataTypeField> systemFieldList) {
assert (fieldNameList == null)
|| (fieldNameList.size()
== (systemFieldList.size() + leftType.getFieldCount() + rightType.getFieldCount()));
List<String> nameList = new ArrayList<>();
final List<RelDataType> typeList = new ArrayList<>();
// Use a set to keep track of the field names; this is needed
// to ensure that the contains() call to check for name uniqueness
// runs in constant time; otherwise, if the number of fields is large,
// doing a contains() on a list can be expensive.
final Set<String> uniqueNameList =
typeFactory.getTypeSystem().isSchemaCaseSensitive()
? new HashSet<String>()
: new TreeSet<>(String.CASE_INSENSITIVE_ORDER);
addFields(systemFieldList, typeList, nameList, uniqueNameList);
addFields(leftType.getFieldList(), typeList, nameList, uniqueNameList);
if (rightType != null) {
addFields(rightType.getFieldList(), typeList, nameList, uniqueNameList);
}
if (fieldNameList != null) {
assert fieldNameList.size() == nameList.size();
nameList = fieldNameList;
}
return typeFactory.createStructType(typeList, nameList);
}
public Type getJavaClass(RelDataType type) {
if (type instanceof JavaType) {
JavaType javaType = (JavaType) type;
return javaType.getJavaClass();
}
if (type.isStruct() && type.getFieldCount() == 1) {
return getJavaClass(type.getFieldList().get(0).getType());
}
if (type instanceof BasicSqlType || type instanceof IntervalSqlType) {
switch (type.getSqlTypeName()) {
case VARCHAR:
case CHAR:
return String.class;
case DATE:
case TIME:
case INTEGER:
case INTERVAL_YEAR_MONTH:
return type.isNullable() ? Integer.class : int.class;
case TIMESTAMP:
case BIGINT:
case INTERVAL_DAY_TIME:
return type.isNullable() ? Long.class : long.class;
case SMALLINT:
return type.isNullable() ? Short.class : short.class;
case TINYINT:
return type.isNullable() ? Byte.class : byte.class;
case DECIMAL:
return BigDecimal.class;
case BOOLEAN:
return type.isNullable() ? Boolean.class : boolean.class;
case DOUBLE:
case FLOAT: // sic
return type.isNullable() ? Double.class : double.class;
case REAL:
return type.isNullable() ? Float.class : float.class;
case BINARY:
case VARBINARY:
return ByteString.class;
case ARRAY:
return Array.class;
case ANY:
return Object.class;
}
}
switch (type.getSqlTypeName()) {
case ROW:
assert type instanceof RelRecordType;
if (type instanceof JavaRecordType) {
return ((JavaRecordType) type).clazz;
} else {
return createSyntheticType((RelRecordType) type);
}
case MAP:
return Map.class;
case ARRAY:
case MULTISET:
return List.class;
}
return null;
}
/**
* 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);
}