SQLGROUP BYaggregationtutorial
What is GROUP BY in SQL? Grouping rows for beginners
GROUP BY is the SQL command for "collapse rows into groups and aggregate". Plain words: how to get "how many orders each customer has" in a single query. What you can and can't put in SELECT, the difference from DISTINCT, GROUP BY on multiple columns, and common pitfalls.
1 мин четенеSQL · GROUP BY · aggregation · tutorial
Упражнявай се на реални задачи
Решавай задачи в SQL тренажора с незабавно оценяване и подсказки.
Отвори тренажора
GROUP BYis the SQL command for "collapse identical rows into one and aggregate them". The basic way to get stats: how many orders each customer has, total sales per product, average salary per department.This article is currently in Russian. The full English translation is on the way.