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diff --git a/src/mongo/db/query/stats/scalar_histogram.cpp b/src/mongo/db/query/stats/scalar_histogram.cpp
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+++ b/src/mongo/db/query/stats/scalar_histogram.cpp
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+/**
+ *    Copyright (C) 2022-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    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
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    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 Server Side 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/stats/scalar_histogram.h"
+
+#include "mongo/db/exec/sbe/values/bson.h"
+#include "mongo/db/exec/sbe/values/value.h"
+
+namespace mongo::stats {
+Bucket::Bucket(
+    double equalFreq, double rangeFreq, double cumulativeFreq, double ndv, double cumulativeNDV)
+    : _equalFreq(equalFreq),
+      _rangeFreq(rangeFreq),
+      _cumulativeFreq(cumulativeFreq),
+      _ndv(ndv),
+      _cumulativeNDV(cumulativeNDV) {
+    uassert(6695702, "Invalid equalFreq", _equalFreq >= 0.0);
+    uassert(6695703, "Invalid rangeFreq", _rangeFreq >= 0.0);
+    uassert(6695704, "Invalid ndv", _ndv <= _rangeFreq);
+    uassert(6695705, "Invalid cumulative frequency", _cumulativeFreq >= _equalFreq + _rangeFreq);
+    uassert(6695706, "Invalid cumulative ndv", _cumulativeNDV >= _ndv + 1.0);
+}
+
+std::string Bucket::toString() const {
+    std::ostringstream os;
+    os << "equalFreq: " << _equalFreq << ", rangeFreq: " << _rangeFreq
+       << ", cumulativeFreq: " << _cumulativeFreq << ", ndv: " << _ndv
+       << ", cumulativeNDV: " << _cumulativeNDV;
+    return os.str();
+}
+
+std::string Bucket::dump() const {
+    std::ostringstream os;
+    os << _equalFreq << ", " << _rangeFreq << ", " << _ndv;
+    return os.str();
+}
+
+BSONObj Bucket::serialize() const {
+    BSONObjBuilder bob;
+    bob.appendNumber("boundaryCount", _equalFreq);
+    bob.appendNumber("rangeCount", _rangeFreq);
+    bob.appendNumber("rangeDistincts", _ndv);
+    bob.appendNumber("cumulativeCount", _cumulativeFreq);
+    bob.appendNumber("cumulativeDistincts", _cumulativeNDV);
+    bob.doneFast();
+    return bob.obj();
+}
+
+ScalarHistogram::ScalarHistogram() : ScalarHistogram({}, {}) {}
+
+ScalarHistogram::ScalarHistogram(const StatsHistogram& histogram) {
+    for (const auto& bucket : histogram.getBuckets()) {
+        Bucket b(bucket.getBoundaryCount(),
+                 bucket.getRangeCount(),
+                 bucket.getCumulativeCount(),
+                 bucket.getRangeDistincts(),
+                 bucket.getCumulativeDistincts());
+        _buckets.push_back(std::move(b));
+    }
+    for (const auto& bound : histogram.getBounds()) {
+        // We cannot insert a view here, because the lifetime of the of the bound is shorter than
+        // that of the histogram. In the case of a larger type, e.g. BigString/bsonString, we need
+        // to copy over the entire string as well, not just a pointer to memory which may be
+        // deallocated before we need it.
+        auto value = sbe::bson::convertFrom<false>(bound.getElement());
+        _bounds.push_back(value.first, value.second);
+    }
+}
+
+ScalarHistogram::ScalarHistogram(sbe::value::Array bounds, std::vector<Bucket> buckets)
+    : _bounds(std::move(bounds)), _buckets(std::move(buckets)) {
+    uassert(6695707, "Invalid sizes", bounds.size() == buckets.size());
+}
+
+std::string ScalarHistogram::toString() const {
+    std::ostringstream os;
+    os << "[";
+    for (size_t i = 0; i < _buckets.size(); i++) {
+        os << "{val: " << _bounds.getAt(i) << ", " << _buckets.at(i).toString() << "}";
+        if (_buckets.size() - i > 1)
+            os << ",";
+    }
+    os << "]";
+    return os.str();
+}
+
+std::string ScalarHistogram::plot() const {
+    std::ostringstream os;
+    double maxFreq = 0;
+    const double maxBucketSize = 100;
+
+    for (const auto& bucket : _buckets) {
+        double maxBucketFreq = std::max(bucket._equalFreq, bucket._rangeFreq);
+        maxFreq = std::max(maxFreq, maxBucketFreq);
+    }
+
+    std::vector<std::pair<double, std::string>> headers;
+    size_t maxHeaderSize = 0;
+    for (size_t i = 0; i < _buckets.size(); ++i) {
+        std::ostringstream rngHeader;
+        std::ostringstream eqlHeader;
+        double scaledRngF = maxBucketSize * _buckets[i]._rangeFreq / maxFreq;
+        double scaledEqlF = maxBucketSize * _buckets[i]._equalFreq / maxFreq;
+        rngHeader << _bounds.getAt(i) << ": " << _buckets[i]._rangeFreq;
+        eqlHeader << _bounds.getAt(i) << ": " << _buckets[i]._equalFreq;
+        auto rngStr = rngHeader.str();
+        maxHeaderSize = std::max(maxHeaderSize, rngStr.size());
+        headers.emplace_back(scaledRngF, rngStr);
+        auto eqlStr = eqlHeader.str();
+        maxHeaderSize = std::max(maxHeaderSize, eqlStr.size());
+        headers.emplace_back(scaledEqlF, eqlStr);
+    }
+
+    const std::string maxLine(maxBucketSize + maxHeaderSize + 3, '-');
+    os << maxLine << "\n";
+    for (size_t j = 0; j < headers.size(); ++j) {
+        auto header = headers.at(j);
+        header.second.resize(maxHeaderSize, ' ');
+        const std::string bar(std::round(header.first), '*');
+        os << header.second << " | " << bar << "\n";
+    }
+    os << maxLine << "\n";
+
+    return os.str();
+}
+
+std::string ScalarHistogram::dump() const {
+    std::ostringstream os;
+    os << "Histogram:\n{";
+    for (size_t i = 0; i < _buckets.size(); i++) {
+        os << "{" << _bounds.getAt(i) << ", " << _buckets.at(i).dump() << "},\n";
+    }
+    os << "}";
+    return os.str();
+}
+
+const sbe::value::Array& ScalarHistogram::getBounds() const {
+    return _bounds;
+}
+
+const std::vector<Bucket>& ScalarHistogram::getBuckets() const {
+    return _buckets;
+}
+
+BSONObj ScalarHistogram::serialize() const {
+    BSONObjBuilder histogramBuilder;
+
+    // Construct bucket BSON.
+    auto buckets = getBuckets();
+    BSONArrayBuilder bucketsBuilder(histogramBuilder.subarrayStart("buckets"));
+    for (const auto& bucket : buckets) {
+        bucketsBuilder.append(bucket.serialize());
+    }
+    bucketsBuilder.doneFast();
+
+    // Construct bucket bounds BSON.
+    auto bounds = getBounds();
+    BSONArrayBuilder boundsBuilder(histogramBuilder.subarrayStart("bounds"));
+    sbe::bson::convertToBsonObj(boundsBuilder, &bounds);
+    boundsBuilder.doneFast();
+
+    histogramBuilder.doneFast();
+    return histogramBuilder.obj();
+}
+
+}  // namespace mongo::stats