GROUP BY : SQL Aggregation for Common Values

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The GROUP BY clause is used to project rows having common values into a smaller set of rows. GROUP BY is often used in conjunction with SQL aggregation functions or to eliminate duplicate rows from a result set. The WHERE clause is applied before the GROUP BY clause.

Depending on the Dialect of SQL, modifiers and functions can be applied to GROUP BY.

Functions can include: MAX(), MIN(), COUNT(), AVG(), SUM(), etc.

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