Alexander Taran AlexanderTaran2
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| Билет №1 — Поиск дублей | |
| Теория: GROUP BY, HAVING COUNT(*) > 1, GROUP_CONCAT | |
| Практика (SQL): | |
| sql | |
| CREATE TABLE products ( | |
| id INTEGER PRIMARY KEY AUTOINCREMENT, | |
| name TEXT NOT NULL | |
| ); |
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| Билет №1 — Поиск дублей | |
| Синтаксис: | |
| sql | |
| SELECT поле, COUNT(*), GROUP_CONCAT(id) | |
| FROM таблица | |
| GROUP BY поле | |
| HAVING COUNT(*) > 1; | |
| Пример из наших решений: |