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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">inttrans</journal-id><journal-title-group><journal-title xml:lang="ru">Интеллектуальный транспорт</journal-title><trans-title-group xml:lang="en"><trans-title>Intelligent transport</trans-title></trans-title-group></journal-title-group><issn pub-type="epub">3033-6007</issn><publisher><publisher-name>АО «НИИАС»</publisher-name></publisher></journal-meta><article-meta><article-id custom-type="edn" pub-id-type="custom">NYDIOB</article-id><article-id custom-type="elpub" pub-id-type="custom">inttrans-107</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ЦИФРОВЫЕ МЕТОДЫ НА ЖЕЛЕЗНОДОРОЖНОМ ТРАНСПОРТЕ</subject></subj-group></article-categories><title-group><article-title>ОЦЕНКА ПЛАНОВ ВЫПОЛНЕНИЯ SQL ЗАПРОСОВ ДЛЯ РЕШЕНИЯ ТРАНСПОРТНЫХ ЗАДАЧ</article-title><trans-title-group xml:lang="en"><trans-title>EVALUATION OF EXECUTION PLANS OF SQL QUERY FOR SOLVING TRANSPORT PROBLEMS</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Дулин</surname><given-names>С. К.</given-names></name><name name-style="western" xml:lang="en"><surname>Dulin</surname><given-names>S. K.</given-names></name></name-alternatives><bio xml:lang="ru"><p>д.т.н., профессор, главный научный сотрудник</p></bio><bio xml:lang="en"><p>D.ofSci., Professor, Chief Researcher</p></bio><email xlink:type="simple">skdulin@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Рябцев</surname><given-names>А. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Ryabtsev</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>аспирант</p></bio><bio xml:lang="en"><p>Postgraduate student</p></bio><email xlink:type="simple">antr5@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>АО «НИИАС»; ИПИ ФИЦ ИУ РАН</institution><country>Россия</country></aff><aff xml:lang="en"><institution>JSC «NIIAS»; Federal Research Center "Informatics and Management" of the RAS</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Московский физико-технический институт (МФТИ)</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Moscow Institute of Physics and Technology (MIPT)</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2023</year></pub-date><pub-date pub-type="epub"><day>15</day><month>09</month><year>2026</year></pub-date><volume>0</volume><issue>1(25)</issue><fpage>38</fpage><lpage>43</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Дулин С.К., Рябцев А.Б., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Дулин С.К., Рябцев А.Б.</copyright-holder><copyright-holder xml:lang="en">Dulin S.K., Ryabtsev A.V.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.intelligent-transport.ru/jour/article/view/107">https://www.intelligent-transport.ru/jour/article/view/107</self-uri><abstract><p>Существующие подходы к проблеме поиска оптимального плана выполнения SQL запроса далеки от идеала. Учитывая многопараметрический характер транспортных задач, минимизация времени выполнения запроса может иметь решающее значение. Функция стоимости, которая каждому плану ставит в соответствие время его выполнения должна удовлетворять следующим требованиям: 1) отношение порядка стоимостей должно как можно больше совпадать с отношением порядка времени, 2) стоимость любого плана не может быть больше стоимости другого плана, полученного путём добавления операций соединений. В работе рассматривается задача оптимизации планов выполнения SQL запросов с помощью методов машинного обучения. В работе подробно описан традиционный подход к решению данной задачи, рассмотрены его недостатки. Также приведён анализ существующих методов машинного обучения, которые призваны устранить ряд недостатков традиционного оптимизатора. Рассмотрены их преимущества и недостатки.</p></abstract><trans-abstract xml:lang="en"><p>Existing approaches to the problem of finding a good SQL query execution plan are far from ideal. Given the multi-parameter nature of transport problems, the optimal plan that minimizes query execution time can be critical. The cost function that associates each plan with its execution time must satisfy the following requirements: 1) the order of cost ratio should match the order of time as much as possible, 2) the cost of any plan cannot be greater than the cost of another plan obtained by adding join operations. The paper considers the problem of optimizing SQL query execution plans using machine learning methods. The paper describes in detail the traditional approach to solving this problem, and considers its shortcomings. An analysis of existing machine learning methods is also given, which are designed to eliminate a number of shortcomings of the traditional optimizer. Their advantages and disadvantages are considered</p></trans-abstract><kwd-group xml:lang="ru"><kwd>ТРАНСПОРТ</kwd><kwd>ОПТИМАЛЬНЫЙ ПЛАН ВЫПОЛНЕНИЯ ЗАПРОСА</kwd><kwd>ФУНКЦИЯ СТОИМОСТИ</kwd><kwd>МЕТОДЫ МАШИННОГО ОБУЧЕНИЯ</kwd><kwd>КАРДИНАЛЬНОСТЬ ТАБЛИЦЫ</kwd></kwd-group><kwd-group xml:lang="en"><kwd>TRANSPORT</kwd><kwd>OPTIMAL QUERY EXECUTION PLAN</kwd><kwd>COST FUNCTION</kwd><kwd>MACHINE LEARNING METHODS</kwd><kwd>TABLE CARDINALITY</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">M Muralikrishna and David J DeWitt. Equi-depth multidimensional histograms. Proceedings of the 1988 ACM SIGMOD international conference on Management of data. 1988, pp.28–36.</mixed-citation><mixed-citation xml:lang="en">M Muralikrishna and David J DeWitt. Equi-depth multidimensional histograms. 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