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Library/Kiến trúc & Database/Cơ sở dữ liệu
Medium Pro#database

Cách dùng GROUP BY trong SQL và phân biệt ROLLUP, CUBE, GROUPING SETS?

February 15, 2026

Quick summary

`GROUP BY` groups rows with identical values into summary rows; every column in the `SELECT` clause must be in the `GROUP BY` clause or an aggregate function. For multi-dimensional reporting, use `ROLLUP` (hierarchical subtotals), `CUBE` (all possible combinations), or `GROUPING SETS` (custom grouping combinations).

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