path: root/src/mongo/db/query/query_solution.cpp

/**
 *    Copyright (C) 2013 10gen Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */

#include "mongo/db/query/query_solution.h"

#include "mongo/db/index_names.h"
#include "mongo/db/matcher/expression_geo.h"
#include "mongo/db/query/planner_analysis.h"
#include "mongo/db/query/query_planner_common.h"

namespace mongo {

using std::set;

string QuerySolutionNode::toString() const {
    mongoutils::str::stream ss;
    appendToString(&ss, 0);
    return ss;
}

// static
void QuerySolutionNode::addIndent(mongoutils::str::stream* ss, int level) {
    for (int i = 0; i < level; ++i) {
        *ss << "---";
    }
}

void QuerySolutionNode::addCommon(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent + 1);
    *ss << "fetched = " << fetched() << '\n';
    addIndent(ss, indent + 1);
    *ss << "sortedByDiskLoc = " << sortedByDiskLoc() << '\n';
    addIndent(ss, indent + 1);
    *ss << "getSort = [";
    for (BSONObjSet::const_iterator it = getSort().begin(); it != getSort().end(); it++) {
        *ss << it->toString() << ", ";
    }
    *ss << "]" << '\n';
}

//
// TextNode
//

void TextNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "TEXT\n";
    addIndent(ss, indent + 1);
    *ss << "keyPattern = " << indexKeyPattern.toString() << '\n';
    addIndent(ss, indent + 1);
    *ss << "query = " << query << '\n';
    addIndent(ss, indent + 1);
    *ss << "language = " << language << '\n';
    addIndent(ss, indent + 1);
    *ss << "caseSensitive= " << caseSensitive << '\n';
    addIndent(ss, indent + 1);
    *ss << "indexPrefix = " << indexPrefix.toString() << '\n';
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        *ss << " filter = " << filter->toString();
    }
    addCommon(ss, indent);
}

QuerySolutionNode* TextNode::clone() const {
    TextNode* copy = new TextNode();
    cloneBaseData(copy);

    copy->_sort = this->_sort;
    copy->indexKeyPattern = this->indexKeyPattern;
    copy->query = this->query;
    copy->language = this->language;
    copy->caseSensitive = this->caseSensitive;
    copy->indexPrefix = this->indexPrefix;

    return copy;
}

//
// CollectionScanNode
//

CollectionScanNode::CollectionScanNode() : tailable(false), direction(1), maxScan(0) {}

void CollectionScanNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "COLLSCAN\n";
    addIndent(ss, indent + 1);
    *ss << "ns = " << name << '\n';
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        *ss << "filter = " << filter->toString();
    }
    addCommon(ss, indent);
}

QuerySolutionNode* CollectionScanNode::clone() const {
    CollectionScanNode* copy = new CollectionScanNode();
    cloneBaseData(copy);

    copy->_sort = this->_sort;
    copy->name = this->name;
    copy->tailable = this->tailable;
    copy->direction = this->direction;
    copy->maxScan = this->maxScan;

    return copy;
}

//
// AndHashNode
//

AndHashNode::AndHashNode() {}

AndHashNode::~AndHashNode() {}

void AndHashNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "AND_HASH\n";
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        *ss << " filter = " << filter->toString() << '\n';
    }
    addCommon(ss, indent);
    for (size_t i = 0; i < children.size(); ++i) {
        addIndent(ss, indent + 1);
        *ss << "Child " << i << ":\n";
        children[i]->appendToString(ss, indent + 1);
    }
}

bool AndHashNode::fetched() const {
    // Any WSM output from this stage came from all children stages.  If any child provides
    // fetched data, we merge that fetched data into the WSM we output.
    for (size_t i = 0; i < children.size(); ++i) {
        if (children[i]->fetched()) {
            return true;
        }
    }
    return false;
}

bool AndHashNode::hasField(const string& field) const {
    // Any WSM output from this stage came from all children stages.  Therefore we have all
    // fields covered in our children.
    for (size_t i = 0; i < children.size(); ++i) {
        if (children[i]->hasField(field)) {
            return true;
        }
    }
    return false;
}

QuerySolutionNode* AndHashNode::clone() const {
    AndHashNode* copy = new AndHashNode();
    cloneBaseData(copy);

    copy->_sort = this->_sort;

    return copy;
}

//
// AndSortedNode
//

AndSortedNode::AndSortedNode() {}

AndSortedNode::~AndSortedNode() {}

void AndSortedNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "AND_SORTED\n";
    addCommon(ss, indent);
    for (size_t i = 0; i < children.size(); ++i) {
        addIndent(ss, indent + 1);
        *ss << "Child " << i << ":\n";
        children[i]->appendToString(ss, indent + 1);
    }
}

bool AndSortedNode::fetched() const {
    // Any WSM output from this stage came from all children stages.  If any child provides
    // fetched data, we merge that fetched data into the WSM we output.
    for (size_t i = 0; i < children.size(); ++i) {
        if (children[i]->fetched()) {
            return true;
        }
    }
    return false;
}

bool AndSortedNode::hasField(const string& field) const {
    // Any WSM output from this stage came from all children stages.  Therefore we have all
    // fields covered in our children.
    for (size_t i = 0; i < children.size(); ++i) {
        if (children[i]->hasField(field)) {
            return true;
        }
    }
    return false;
}

QuerySolutionNode* AndSortedNode::clone() const {
    AndSortedNode* copy = new AndSortedNode();
    cloneBaseData(copy);

    copy->_sort = this->_sort;

    return copy;
}

//
// OrNode
//

OrNode::OrNode() : dedup(true) {}

OrNode::~OrNode() {}

void OrNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "OR\n";
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        *ss << " filter = " << filter->toString() << '\n';
    }
    addCommon(ss, indent);
    for (size_t i = 0; i < children.size(); ++i) {
        addIndent(ss, indent + 1);
        *ss << "Child " << i << ":\n";
        children[i]->appendToString(ss, indent + 2);
        *ss << '\n';
    }
}

bool OrNode::fetched() const {
    // Any WSM output from this stage came exactly one child stage.  Given that we don't know
    // what child stage it came from, we require that all children provide fetched data in order
    // to guarantee that our output is fetched.
    for (size_t i = 0; i < children.size(); ++i) {
        if (!children[i]->fetched()) {
            return false;
        }
    }
    return true;
}

/**
 * Any WSM output from this stage came from exactly one child stage.  Therefore, if
 * we want to guarantee that any output has a certain field, all of our children must
 * have that field.
 */
bool OrNode::hasField(const string& field) const {
    for (size_t i = 0; i < children.size(); ++i) {
        if (!children[i]->hasField(field)) {
            return false;
        }
    }
    return true;
}

QuerySolutionNode* OrNode::clone() const {
    OrNode* copy = new OrNode();
    cloneBaseData(copy);

    copy->_sort = this->_sort;
    copy->dedup = this->dedup;

    return copy;
}

//
// MergeSortNode
//

MergeSortNode::MergeSortNode() : dedup(true) {}

MergeSortNode::~MergeSortNode() {}

void MergeSortNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "MERGE_SORT\n";
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        *ss << " filter = " << filter->toString() << '\n';
    }
    addCommon(ss, indent);
    for (size_t i = 0; i < children.size(); ++i) {
        addIndent(ss, indent + 1);
        *ss << "Child " << i << ":\n";
        children[i]->appendToString(ss, indent + 2);
        *ss << '\n';
    }
}

bool MergeSortNode::fetched() const {
    // Any WSM output from this stage came exactly one child stage.  Given that we don't know
    // what child stage it came from, we require that all children provide fetched data in order
    // to guarantee that our output is fetched.
    for (size_t i = 0; i < children.size(); ++i) {
        if (!children[i]->fetched()) {
            return false;
        }
    }
    return true;
}

/**
 * Any WSM output from this stage came from exactly one child stage.  Therefore, if
 * we want to guarantee that any output has a certain field, all of our children must
 * have that field.
 */
bool MergeSortNode::hasField(const string& field) const {
    for (size_t i = 0; i < children.size(); ++i) {
        if (!children[i]->hasField(field)) {
            return false;
        }
    }
    return true;
}

QuerySolutionNode* MergeSortNode::clone() const {
    MergeSortNode* copy = new MergeSortNode();
    cloneBaseData(copy);

    copy->_sorts = this->_sorts;
    copy->dedup = this->dedup;
    copy->sort = this->sort;

    return copy;
}

//
// FetchNode
//

FetchNode::FetchNode() {}

void FetchNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "FETCH\n";
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        StringBuilder sb;
        *ss << "filter:\n";
        filter->debugString(sb, indent + 2);
        *ss << sb.str();
    }
    addCommon(ss, indent);
    addIndent(ss, indent + 1);
    *ss << "Child:" << '\n';
    children[0]->appendToString(ss, indent + 2);
}

QuerySolutionNode* FetchNode::clone() const {
    FetchNode* copy = new FetchNode();
    cloneBaseData(copy);

    copy->_sorts = this->_sorts;

    return copy;
}

//
// IndexScanNode
//

IndexScanNode::IndexScanNode()
    : indexIsMultiKey(false), direction(1), maxScan(0), addKeyMetadata(false) {}

void IndexScanNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "IXSCAN\n";
    addIndent(ss, indent + 1);
    *ss << "keyPattern = " << indexKeyPattern << '\n';
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        *ss << "filter = " << filter->toString();
    }
    addIndent(ss, indent + 1);
    *ss << "direction = " << direction << '\n';
    addIndent(ss, indent + 1);
    *ss << "bounds = " << bounds.toString() << '\n';
    addCommon(ss, indent);
}

bool IndexScanNode::hasField(const string& field) const {
    // There is no covering in a multikey index because you don't know whether or not the field
    // in the key was extracted from an array in the original document.
    if (indexIsMultiKey) {
        return false;
    }

    // Custom index access methods may return non-exact key data - this function is currently
    // used for covering exact key data only.
    if (IndexNames::BTREE != IndexNames::findPluginName(indexKeyPattern)) {
        return false;
    }

    BSONObjIterator it(indexKeyPattern);
    while (it.more()) {
        if (field == it.next().fieldName()) {
            return true;
        }
    }
    return false;
}

bool IndexScanNode::sortedByDiskLoc() const {
    // Indices use RecordId as an additional key after the actual index key.
    // Therefore, if we're only examining one index key, the output is sorted
    // by RecordId.

    // If it's a simple range query, it's easy to determine if the range is a point.
    if (bounds.isSimpleRange) {
        return 0 == bounds.startKey.woCompare(bounds.endKey, indexKeyPattern);
    }

    // If it's a more complex bounds query, we make sure that each field is a point.
    for (size_t i = 0; i < bounds.fields.size(); ++i) {
        const OrderedIntervalList& oil = bounds.fields[i];
        if (1 != oil.intervals.size()) {
            return false;
        }
        const Interval& interval = oil.intervals[0];
        if (0 != interval.start.woCompare(interval.end, false)) {
            return false;
        }
    }

    return true;
}

void IndexScanNode::computeProperties() {
    _sorts.clear();

    BSONObj sortPattern = QueryPlannerAnalysis::getSortPattern(indexKeyPattern);
    if (direction == -1) {
        sortPattern = QueryPlannerCommon::reverseSortObj(sortPattern);
    }

    _sorts.insert(sortPattern);

    const int nFields = sortPattern.nFields();
    if (nFields > 1) {
        // We're sorted not only by sortPattern but also by all prefixes of it.
        for (int i = 0; i < nFields; ++i) {
            // Make obj out of fields [0,i]
            BSONObjIterator it(sortPattern);
            BSONObjBuilder prefixBob;
            for (int j = 0; j <= i; ++j) {
                prefixBob.append(it.next());
            }
            _sorts.insert(prefixBob.obj());
        }
    }

    // If we are using the index {a:1, b:1} to answer the predicate {a: 10}, it's sorted
    // both by the index key pattern and by the pattern {b: 1}.

    // See if there are any fields with equalities for bounds.  We can drop these
    // from any sort orders created.
    set<string> equalityFields;
    if (!bounds.isSimpleRange) {
        // Figure out how many fields are point intervals.
        for (size_t i = 0; i < bounds.fields.size(); ++i) {
            const OrderedIntervalList& oil = bounds.fields[i];
            if (oil.intervals.size() != 1) {
                continue;
            }
            const Interval& ival = oil.intervals[0];
            if (!ival.isPoint()) {
                continue;
            }
            equalityFields.insert(oil.name);
        }
    }

    if (equalityFields.empty()) {
        return;
    }

    // TODO: Each field in equalityFields could be dropped from the sort order since it is
    // a point interval.  The full set of sort orders is as follows:
    // For each sort in _sorts:
    //    For each drop in powerset(equalityFields):
    //        Remove fields in 'drop' from 'sort' and add resulting sort to output.
    //
    // Since this involves a powerset, we don't generate the full set of possibilities.
    // Instead, we generate sort orders by removing possible contiguous prefixes of equality
    // predicates. For example, if the key pattern is {a: 1, b: 1, c: 1, d: 1, e: 1}
    // and and there are equality predicates on 'a', 'b', and 'c', then here we add the sort
    // orders {b: 1, c: 1, d: 1, e: 1} and {c: 1, d: 1, e: 1}. (We also end up adding
    // {d: 1, e: 1} and {d: 1}, but this is done later on.)
    BSONObjIterator it(sortPattern);
    BSONObjBuilder suffixBob;
    while (it.more()) {
        BSONElement elt = it.next();
        // TODO: string slowness.  fix when bounds are stringdata not string.
        if (equalityFields.end() == equalityFields.find(string(elt.fieldName()))) {
            suffixBob.append(elt);
            // This field isn't a point interval, can't drop.
            break;
        }

        // We add the sort obtained by dropping 'elt' and all preceding elements from the index
        // key pattern.
        BSONObjIterator droppedPrefixIt = it;
        BSONObjBuilder droppedPrefixBob;
        while (droppedPrefixIt.more()) {
            droppedPrefixBob.append(droppedPrefixIt.next());
        }
        _sorts.insert(droppedPrefixBob.obj());
    }

    while (it.more()) {
        suffixBob.append(it.next());
    }

    // We've found the suffix following the contiguous prefix of equality fields.
    //   Ex. For index {a: 1, b: 1, c: 1, d: 1} and query {a: 3, b: 5}, this suffix
    //   of the key pattern is {c: 1, d: 1}.
    //
    // Now we have to add all prefixes of this suffix as possible sort orders.
    //   Ex. Continuing the example from above, we have to include sort orders
    //   {c: 1} and {c: 1, d: 1}.
    BSONObj filterPointsObj = suffixBob.obj();
    for (int i = 0; i < filterPointsObj.nFields(); ++i) {
        // Make obj out of fields [0,i]
        BSONObjIterator it(filterPointsObj);
        BSONObjBuilder prefixBob;
        for (int j = 0; j <= i; ++j) {
            prefixBob.append(it.next());
        }
        _sorts.insert(prefixBob.obj());
    }
}

QuerySolutionNode* IndexScanNode::clone() const {
    IndexScanNode* copy = new IndexScanNode();
    cloneBaseData(copy);

    copy->_sorts = this->_sorts;
    copy->indexKeyPattern = this->indexKeyPattern;
    copy->indexIsMultiKey = this->indexIsMultiKey;
    copy->direction = this->direction;
    copy->maxScan = this->maxScan;
    copy->addKeyMetadata = this->addKeyMetadata;
    copy->bounds = this->bounds;

    return copy;
}

//
// ProjectionNode
//

void ProjectionNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "PROJ\n";
    addIndent(ss, indent + 1);
    *ss << "proj = " << projection.toString() << '\n';
    addIndent(ss, indent + 1);
    if (DEFAULT == projType) {
        *ss << "type = DEFAULT\n";
    } else if (COVERED_ONE_INDEX == projType) {
        *ss << "type = COVERED_ONE_INDEX\n";
    } else {
        invariant(SIMPLE_DOC == projType);
        *ss << "type = SIMPLE_DOC\n";
    }
    addCommon(ss, indent);
    addIndent(ss, indent + 1);
    *ss << "Child:" << '\n';
    children[0]->appendToString(ss, indent + 2);
}

QuerySolutionNode* ProjectionNode::clone() const {
    ProjectionNode* copy = new ProjectionNode();
    cloneBaseData(copy);

    copy->_sorts = this->_sorts;
    copy->fullExpression = this->fullExpression;

    // This MatchExpression* is owned by the canonical query, not by the
    // ProjectionNode. Just copying the pointer is fine.
    copy->projection = this->projection;

    return copy;
}

//
// SortNode
//

void SortNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "SORT\n";
    addIndent(ss, indent + 1);
    *ss << "pattern = " << pattern.toString() << '\n';
    addIndent(ss, indent + 1);
    *ss << "query for bounds = " << query.toString() << '\n';
    addIndent(ss, indent + 1);
    *ss << "limit = " << limit << '\n';
    addCommon(ss, indent);
    addIndent(ss, indent + 1);
    *ss << "Child:" << '\n';
    children[0]->appendToString(ss, indent + 2);
}

QuerySolutionNode* SortNode::clone() const {
    SortNode* copy = new SortNode();
    cloneBaseData(copy);

    copy->_sorts = this->_sorts;
    copy->pattern = this->pattern;
    copy->query = this->query;
    copy->limit = this->limit;

    return copy;
}

//
// LimitNode
//


void LimitNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "LIMIT\n";
    addIndent(ss, indent + 1);
    *ss << "limit = " << limit << '\n';
    addIndent(ss, indent + 1);
    addCommon(ss, indent);
    addIndent(ss, indent + 1);
    *ss << "Child:" << '\n';
    children[0]->appendToString(ss, indent + 2);
}

QuerySolutionNode* LimitNode::clone() const {
    LimitNode* copy = new LimitNode();
    cloneBaseData(copy);

    copy->limit = this->limit;

    return copy;
}

//
// SkipNode
//

void SkipNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "SKIP\n";
    addIndent(ss, indent + 1);
    *ss << "skip= " << skip << '\n';
    addCommon(ss, indent);
    addIndent(ss, indent + 1);
    *ss << "Child:" << '\n';
    children[0]->appendToString(ss, indent + 2);
}

QuerySolutionNode* SkipNode::clone() const {
    SkipNode* copy = new SkipNode();
    cloneBaseData(copy);

    copy->skip = this->skip;

    return copy;
}

//
// GeoNear2DNode
//

void GeoNear2DNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "GEO_NEAR_2D\n";
    addIndent(ss, indent + 1);
    *ss << "keyPattern = " << indexKeyPattern.toString() << '\n';
    addCommon(ss, indent);
    *ss << "nearQuery = " << nq->toString() << '\n';
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        *ss << " filter = " << filter->toString();
    }
}

QuerySolutionNode* GeoNear2DNode::clone() const {
    GeoNear2DNode* copy = new GeoNear2DNode();
    cloneBaseData(copy);

    copy->_sorts = this->_sorts;
    copy->nq = this->nq;
    copy->baseBounds = this->baseBounds;
    copy->indexKeyPattern = this->indexKeyPattern;
    copy->addPointMeta = this->addPointMeta;
    copy->addDistMeta = this->addDistMeta;

    return copy;
}

//
// GeoNear2DSphereNode
//

void GeoNear2DSphereNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "GEO_NEAR_2DSPHERE\n";
    addIndent(ss, indent + 1);
    *ss << "keyPattern = " << indexKeyPattern.toString() << '\n';
    addCommon(ss, indent);
    *ss << "baseBounds = " << baseBounds.toString() << '\n';
    addIndent(ss, indent + 1);
    *ss << "nearQuery = " << nq->toString() << '\n';
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        *ss << " filter = " << filter->toString();
    }
}

QuerySolutionNode* GeoNear2DSphereNode::clone() const {
    GeoNear2DSphereNode* copy = new GeoNear2DSphereNode();
    cloneBaseData(copy);

    copy->_sorts = this->_sorts;
    copy->nq = this->nq;
    copy->baseBounds = this->baseBounds;
    copy->indexKeyPattern = this->indexKeyPattern;
    copy->addPointMeta = this->addPointMeta;
    copy->addDistMeta = this->addDistMeta;

    return copy;
}

//
// ShardingFilterNode
//

void ShardingFilterNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "SHARDING_FILTER\n";
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        StringBuilder sb;
        *ss << "filter:\n";
        filter->debugString(sb, indent + 2);
        *ss << sb.str();
    }
    addCommon(ss, indent);
    addIndent(ss, indent + 1);
    *ss << "Child:" << '\n';
    children[0]->appendToString(ss, indent + 2);
}

QuerySolutionNode* ShardingFilterNode::clone() const {
    ShardingFilterNode* copy = new ShardingFilterNode();
    cloneBaseData(copy);
    return copy;
}

//
// KeepMutationsNode
//

void KeepMutationsNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "KEEP_MUTATIONS\n";
    if (NULL != filter) {
        addIndent(ss, indent + 1);
        StringBuilder sb;
        *ss << "filter:\n";
        filter->debugString(sb, indent + 2);
        *ss << sb.str();
    }
    addCommon(ss, indent);
    addIndent(ss, indent + 1);
    *ss << "Child:" << '\n';
    children[0]->appendToString(ss, indent + 2);
}

QuerySolutionNode* KeepMutationsNode::clone() const {
    KeepMutationsNode* copy = new KeepMutationsNode();
    cloneBaseData(copy);

    copy->sorts = this->sorts;

    return copy;
}

//
// DistinctNode
//

void DistinctNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "DISTINCT\n";
    addIndent(ss, indent + 1);
    *ss << "keyPattern = " << indexKeyPattern << '\n';
    addIndent(ss, indent + 1);
    *ss << "direction = " << direction << '\n';
    addIndent(ss, indent + 1);
    *ss << "bounds = " << bounds.toString() << '\n';
}

QuerySolutionNode* DistinctNode::clone() const {
    DistinctNode* copy = new DistinctNode();
    cloneBaseData(copy);

    copy->sorts = this->sorts;
    copy->indexKeyPattern = this->indexKeyPattern;
    copy->direction = this->direction;
    copy->bounds = this->bounds;
    copy->fieldNo = this->fieldNo;

    return copy;
}

//
// CountNode
//

void CountNode::appendToString(mongoutils::str::stream* ss, int indent) const {
    addIndent(ss, indent);
    *ss << "COUNT\n";
    addIndent(ss, indent + 1);
    *ss << "keyPattern = " << indexKeyPattern << '\n';
    addIndent(ss, indent + 1);
    *ss << "startKey = " << startKey << '\n';
    addIndent(ss, indent + 1);
    *ss << "endKey = " << endKey << '\n';
}

QuerySolutionNode* CountNode::clone() const {
    CountNode* copy = new CountNode();
    cloneBaseData(copy);

    copy->sorts = this->sorts;
    copy->indexKeyPattern = this->indexKeyPattern;
    copy->startKey = this->startKey;
    copy->startKeyInclusive = this->startKeyInclusive;
    copy->endKey = this->endKey;
    copy->endKeyInclusive = this->endKeyInclusive;

    return copy;
}

}  // namespace mongo