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What is the statement used to group in mysql

Apr 27, 2024 am 06:18 AM
mysql

The GROUP BY statement in MySQL is used to group data by specified columns and calculate aggregate values ​​for each group, such as totals, sums, and averages.

What is the statement used to group in mysql

The statement used for grouping in MySQL: GROUP BY

The GROUP BY statement in MySQL is used to group data Group by specified columns and calculate aggregate values ​​for each group such as SUM, COUNT, AVG, etc.

Syntax:

SELECT 列名1, 列名2, ...
FROM 表名
GROUP BY 分组列
HAVING 条件(可选)
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Parameters:

  • ##Column name 1, column name 2, . ..: The column to be selected.
  • Table name: The table to be grouped.
  • Grouping column: Column used for grouping.
  • HAVING conditions (optional): Conditions used to filter group results.

How it works:

The GROUP BY statement groups the data in the table by the grouping column and creates a new result set with each group There is only one line. The aggregate value for each group is calculated based on the corresponding values ​​for that group in the original data.

Example:

Suppose we have a table named "sales" that contains the following data:

##Product ID##1Apple1002banana503Apple 754banana25 want To group sales by product name and calculate total sales for each product, you can use the following query:
SELECT 产品名称, SUM(销售额) AS 总销售额
FROM sales
GROUP BY 产品名称;
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Result:

Product Name Sales
Product NameTotal SalesApple175banana75

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