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    Как работает оператор LEFT JOIN в SQL?

    Нейро

    Ответ создан на основе результатов поиска

    Оператор LEFT JOIN в SQL работает так: он объединяет две таблицы на основе общего столбца и выбирает не только записи с совпадающими значениями в этих столбцах, но и все оставшиеся строки из левой таблицы 2.
    Если в правой таблице нет совпадающих строк, результат будет содержать NULL для всех столбцов из правой таблицы 4.
    На основе 10 источников:

      Оценить ответ

      10 источников

      1. w3schools.com
        1
      2. ravesli.com
        2
      3. sky.pro
        3
      4. habr.com
        4
      5. geeksforgeeks.org
        5
      6. learn.microsoft.com
        6
      7. ru.hexlet.io
        7
      8. dev.mysql.com
        8
      9. learnsql.com
        9
      10. sql-tutorial.github.io
        10

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