Which one is executed first, group by or order by?

The execution order of GROUP BY and ORDER BY clauses in SQL queries is: 1. GROUP BY first groups by the specified grouping column and calculates the aggregate value; 2. ORDER BY then sorts the grouped data according to the sorting column. .

In a SQL query, the execution order of theGROUP BYandORDER BYclauses is as follows:

1. GROUP BYFirst execute the

GROUP BYclause to group the data set by the specified grouping column Groups, and calculates the aggregate value for each group (e.g., sums, averages).

2. ORDER BYThen execute the

##ORDER BYclause to group the data set Sort by the specified sort column.

Example:

SELECT SUM(sales) FROM sales_data GROUP BY product_id ORDER BY product_id;

1. GROUP BY product_idGroup the data set byproduct_idGroups and calculates the total sales for each group.
2. ORDER BY product_idSort the grouped data set in ascending order byproduct_id.

product_idin ascending order.

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