#почитать
В этой лекции углубимся в расширенные возможности SELECT:
▫️как "сложить" и "вычесть" выборки (UNION/INTERSECT/EXCEPT)
▫️как запомнить их и использовать повторно (даже в рекурсивных запросах)
▫️что дают оконные функции (WINDOW) и соединения (JOIN)
BY SQL для тестировщика
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SQL для тестировщика from nl