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 min de lectureSQL · GROUP BY · aggregation · tutorial

GROUP BY is 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.

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