Что такое "нормальная форма" БД и какие формы существуют.
▫️Что такое нормализация
▫️Что такое избыточность данных - примеры
▫️Какие бывают нормальные формы БД
▫️Ненормализованная форма
▫️Пример нормальной формы
▫️Еще пример
▫️Что такое декомпозиция
▫️Нормальная форма Бойса-Кодда
▫️Четвертая нормальная форма
▫️Почему обычно не нормализуют до 5 или 6 формы
▫️Пятая и шестая нормальная формы
BY SQL для тестировщика
Telegram is an aspiring new messaging app that’s taking the world by storm. The app is free, fast, and claims to be one of the safest messengers around. It allows people to connect easily, without any boundaries.You can use channels on Telegram, which are similar to Facebook pages. If you’re wondering how to find channels on Telegram, you’re in the right place. Keep reading and you’ll find out how. Also, you’ll learn more about channels, creating channels yourself, and the difference between private and public Telegram channels.
The lead from Wall Street offers little clarity as the major averages opened lower on Friday and then bounced back and forth across the unchanged line, finally finishing mixed and little changed.The Dow added 33.18 points or 0.10 percent to finish at 34,798.00, while the NASDAQ eased 4.54 points or 0.03 percent to close at 15,047.70 and the S&P 500 rose 6.50 points or 0.15 percent to end at 4,455.48. For the week, the Dow rose 0.6 percent, the NASDAQ added 0.1 percent and the S&P gained 0.5 percent.The lackluster performance on Wall Street came on uncertainty about the outlook for the markets following recent volatility.
SQL для тестировщика from fr